Cutis

The Diagnosis: Lichen Planus Pemphigoides

Lichen planus pemphigoides (LPP) is a rare acquired autoimmune blistering disorder with an estimated worldwide prevalence of approximately 1 in 1,000,000 individuals.¹ It often manifests with overlapping features of both LP and bullous pemphigoid (BP). The condition usually presents in the fifth decade of life and has a slight female predominance.² Although primarily idiopathic, it has been associated with certain medications and treatments, such as angiotensin-converting enzyme inhibitors, programmed cell death protein 1 inhibitors, programmed cell death ligand 1 inhibitors, labetalol, narrowband UVB, and psoralen plus UVA.^3,4

Patients initially present with lesions of classic lichen planus (LP) with pink-purple, flat-topped, pruritic, polygonal papules and plaques.⁵ After weeks to months, tense vesicles and bullae usually develop on the sites of LP as well as on uninvolved skin. One study found a mean lag time of about 8.3 months for blistering to present after LP,⁵ but concurrent presentations of both have been reported.¹ In addition, oral mucosal involvement has been seen in 36% of cases. The most commonly affected sites are the extremities; however, involvement can be widespread.²

The pathogenesis of LPP currently is unknown. It has been proposed that in LP, injury of basal keratinocytes exposes hidden basement membrane and hemidesmosome antigens including BP180, a 180 kDa transmembrane protein of the basement membrane zone (BMZ),⁶ which triggers an immune response where T cells recognize the extracellular portion of BP180 and antibodies are formed against the likely autoantigen.1 One study has suggested that the autoantigen in LPP is the MCW-4 epitope within the C-terminal end of the NC16A domain of BP180.⁷

Histopathology of LPP reveals characteristics of both LP as well as BP. Typical features of LP on hematoxylin and eosin (H&E) staining include lichenoid lymphocytic interface dermatitis, sawtooth rete ridges, wedge-shaped hypergranulosis, and colloid bodies, as demonstrated from the biopsy of our patient’s gluteal cleft lesion (quiz image 1), while the predominant feature of BP on H&E staining includes a subepidermal bulla with eosinophils.² Typically, direct immunofluorescence (DIF) shows linear deposits of IgG and/or C3 along the BMZ. Indirect immunofluorescence (IIF) often reveals IgG against the roof of the BMZ in a human split-skin substrate.¹ Antibodies against BP180 or uncommonly BP230 often are detected on enzyme-linked immunosorbent assay (ELISA). For our patient, IIF and ELISA tests were positive. Given the clinical presentation with recurrent oral and gluteal cleft erosions, histologic findings, and the results of our patient’s immunological testing, the diagnosis of LPP was made.

Topical steroids often are used to treat localized disease of LPP.8 Oral prednisone also may be given for widespread or unresponsive disease.⁹ Other treatments include azathioprine, mycophenolate mofetil, hydroxychloroquine, dapsone, tetracycline in combination with nicotinamide, acitretin, ustekinumab, baricitinib, and rituximab with intravenous immunoglobulin.^3,8,10-12 Any potential medication culprits should be discontinued.⁹ Patients with oral involvement may require a soft diet to avoid further mucosal insult.¹⁰ Additionally, providers should consider dentistry, ophthalmology, and/or otolaryngology referrals depending on disease severity.

Bullous pemphigoid, the most common autoimmune blistering disease, has an estimated incidence of 10 to 43 per million individuals per year.² Classically, it presents with tense bullae on the skin of the lower abdomen, thighs, groin, forearms, and axillae. Circulating antibodies against 2 BMZ proteins—BP180 and BP230—are important factors in BP pathogenesis.² Diagnosis of BP is based on clinical features, histologic findings, and immunological studies including DIF, IIF, and ELISA. An eosinophil-rich subepidermal split typically is seen on H&E staining (Figure 1).

Direct immunofluorescence displays linear IgG and/ or C3 staining at the BMZ. Indirect immunofluorescence on a human salt-split skin substrate commonly shows linear BMZ deposition on the roof of the blister.² Indirect immunofluorescence for IgG deposition on monkey esophagus substrate shows linear BMZ deposition. Antibodies against the NC16A domain of BP180 (NC16A-BP180) are dominant, but BP230 antibodies against BP230 also are detected with ELISA.² Further studies have indicated that the NC16A epitopes of BP180 that are targeted in BP are MCW-0-3,² different from the autoantigen MCW-4 that is targeted in LPP.⁷

Paraneoplastic pemphigus (PNP) is another diagnosis to consider. Patients with PNP initially present with oral findings—most commonly chronic, erosive, and painful mucositis—followed by cutaneous involvement, which varies from the development of bullae to the formation of plaques similar to those of LP.¹³ The latter, in combination with oral erosions, may appear clinically similar to LPP. The results of DIF in conjugation with IIF and ELISA may help to further differentiate these disorders. Direct immunofluorescence in PNP typically reveals positive intercellular and/or BMZ IgG and C3, while DIF in LPP reveals depositions along the BMZ alone. Indirect immunofluorescence performed on rat bladder epithelium is particularly useful, as binding of IgG to rat bladder epithelium is characteristic of PNP and not seen in other disorders.¹⁴ Lastly, patients with PNP may develop IgG antibodies to various antigens such as desmoplakin I, desmoplakin II, envoplakin, periplakin, BP230, desmoglein 1, and desmoglein 3, which would not be expected in LPP patients.¹⁵ Hematoxylin and eosin staining differs from LPP, primarily with the location of the blister being intraepidermal. Acantholysis with hemorrhagic bullae can be seen (Figure 2).

Classic LP is an inflammatory disorder that mainly affects adults, with an estimated incidence of less than 1%.¹⁶ The classic form presents with purple, flat-topped, pruritic, polygonal papules and plaques of varying size that often are characterized by Wickham striae. Lichen planus possesses a broad spectrum of subtypes involving different locations, though skin lesions usually are localized to the extremities. Despite an unknown etiology, activated T cells and T helper type 1 cytokines are considered key in keratinocyte injury. Compact orthokeratosis, wedge-shaped hypergranulosis, focal dyskeratosis, and colloid bodies typically are found on H&E staining, along with a dense bandlike lymphohistiocytic infiltrate at the dermoepidermal junction (DEJ)(Figure 3). Direct immunofluorescence typically shows a shaggy band of fibrinogen along the DEJ in addition to colloid bodies that stain with various autoantibodies including IgM, IgG, IgA, and C3.¹⁶

Bullous LP is a rare variant of LP that commonly develops on the oral mucosa and the legs, with blisters confined on pre-existing LP lesions.⁹ The pathogenesis is related to an epidermal inflammatory infiltrate that leads to basal layer destruction followed by dermal-epidermal separations that cause blistering.¹⁷ Bullous LP does not have positive DIF, IIF, or ELISA because the pathophysiology does not involve autoantibody production. Histopathology typically displays an extensive inflammatory infiltrate and degeneration of the basal keratinocytes, resulting in large dermal-epidermal separations called Max-Joseph spaces (Figure 4).¹⁷ Colloid bodies are prominent in bullous LP but rarely are seen in LPP; eosinophils also are much more prominent in LPP compared to bullous LP.¹⁸ Unlike in LPP, DIF usually is negative in bullous LP, though lichenoid lesions may exhibit globular deposition of IgM, IgG, and IgA in the colloid bodies of the lower epidermis and/or papillary dermis. Similar to LP, DIF of the biopsy specimen shows linear or shaggy deposits of fibrinogen at the DEJ.¹⁷

The Diagnosis: Lichen Planus Pemphigoides

Lichen planus pemphigoides (LPP) is a rare acquired autoimmune blistering disorder with an estimated worldwide prevalence of approximately 1 in 1,000,000 individuals.¹ It often manifests with overlapping features of both LP and bullous pemphigoid (BP). The condition usually presents in the fifth decade of life and has a slight female predominance.² Although primarily idiopathic, it has been associated with certain medications and treatments, such as angiotensin-converting enzyme inhibitors, programmed cell death protein 1 inhibitors, programmed cell death ligand 1 inhibitors, labetalol, narrowband UVB, and psoralen plus UVA.^3,4

Patients initially present with lesions of classic lichen planus (LP) with pink-purple, flat-topped, pruritic, polygonal papules and plaques.⁵ After weeks to months, tense vesicles and bullae usually develop on the sites of LP as well as on uninvolved skin. One study found a mean lag time of about 8.3 months for blistering to present after LP,⁵ but concurrent presentations of both have been reported.¹ In addition, oral mucosal involvement has been seen in 36% of cases. The most commonly affected sites are the extremities; however, involvement can be widespread.²

The pathogenesis of LPP currently is unknown. It has been proposed that in LP, injury of basal keratinocytes exposes hidden basement membrane and hemidesmosome antigens including BP180, a 180 kDa transmembrane protein of the basement membrane zone (BMZ),⁶ which triggers an immune response where T cells recognize the extracellular portion of BP180 and antibodies are formed against the likely autoantigen.1 One study has suggested that the autoantigen in LPP is the MCW-4 epitope within the C-terminal end of the NC16A domain of BP180.⁷

Histopathology of LPP reveals characteristics of both LP as well as BP. Typical features of LP on hematoxylin and eosin (H&E) staining include lichenoid lymphocytic interface dermatitis, sawtooth rete ridges, wedge-shaped hypergranulosis, and colloid bodies, as demonstrated from the biopsy of our patient’s gluteal cleft lesion (quiz image 1), while the predominant feature of BP on H&E staining includes a subepidermal bulla with eosinophils.² Typically, direct immunofluorescence (DIF) shows linear deposits of IgG and/or C3 along the BMZ. Indirect immunofluorescence (IIF) often reveals IgG against the roof of the BMZ in a human split-skin substrate.¹ Antibodies against BP180 or uncommonly BP230 often are detected on enzyme-linked immunosorbent assay (ELISA). For our patient, IIF and ELISA tests were positive. Given the clinical presentation with recurrent oral and gluteal cleft erosions, histologic findings, and the results of our patient’s immunological testing, the diagnosis of LPP was made.

Topical steroids often are used to treat localized disease of LPP.8 Oral prednisone also may be given for widespread or unresponsive disease.⁹ Other treatments include azathioprine, mycophenolate mofetil, hydroxychloroquine, dapsone, tetracycline in combination with nicotinamide, acitretin, ustekinumab, baricitinib, and rituximab with intravenous immunoglobulin.^3,8,10-12 Any potential medication culprits should be discontinued.⁹ Patients with oral involvement may require a soft diet to avoid further mucosal insult.¹⁰ Additionally, providers should consider dentistry, ophthalmology, and/or otolaryngology referrals depending on disease severity.

Bullous pemphigoid, the most common autoimmune blistering disease, has an estimated incidence of 10 to 43 per million individuals per year.² Classically, it presents with tense bullae on the skin of the lower abdomen, thighs, groin, forearms, and axillae. Circulating antibodies against 2 BMZ proteins—BP180 and BP230—are important factors in BP pathogenesis.² Diagnosis of BP is based on clinical features, histologic findings, and immunological studies including DIF, IIF, and ELISA. An eosinophil-rich subepidermal split typically is seen on H&E staining (Figure 1).

Direct immunofluorescence displays linear IgG and/ or C3 staining at the BMZ. Indirect immunofluorescence on a human salt-split skin substrate commonly shows linear BMZ deposition on the roof of the blister.² Indirect immunofluorescence for IgG deposition on monkey esophagus substrate shows linear BMZ deposition. Antibodies against the NC16A domain of BP180 (NC16A-BP180) are dominant, but BP230 antibodies against BP230 also are detected with ELISA.² Further studies have indicated that the NC16A epitopes of BP180 that are targeted in BP are MCW-0-3,² different from the autoantigen MCW-4 that is targeted in LPP.⁷

Paraneoplastic pemphigus (PNP) is another diagnosis to consider. Patients with PNP initially present with oral findings—most commonly chronic, erosive, and painful mucositis—followed by cutaneous involvement, which varies from the development of bullae to the formation of plaques similar to those of LP.¹³ The latter, in combination with oral erosions, may appear clinically similar to LPP. The results of DIF in conjugation with IIF and ELISA may help to further differentiate these disorders. Direct immunofluorescence in PNP typically reveals positive intercellular and/or BMZ IgG and C3, while DIF in LPP reveals depositions along the BMZ alone. Indirect immunofluorescence performed on rat bladder epithelium is particularly useful, as binding of IgG to rat bladder epithelium is characteristic of PNP and not seen in other disorders.¹⁴ Lastly, patients with PNP may develop IgG antibodies to various antigens such as desmoplakin I, desmoplakin II, envoplakin, periplakin, BP230, desmoglein 1, and desmoglein 3, which would not be expected in LPP patients.¹⁵ Hematoxylin and eosin staining differs from LPP, primarily with the location of the blister being intraepidermal. Acantholysis with hemorrhagic bullae can be seen (Figure 2).

Classic LP is an inflammatory disorder that mainly affects adults, with an estimated incidence of less than 1%.¹⁶ The classic form presents with purple, flat-topped, pruritic, polygonal papules and plaques of varying size that often are characterized by Wickham striae. Lichen planus possesses a broad spectrum of subtypes involving different locations, though skin lesions usually are localized to the extremities. Despite an unknown etiology, activated T cells and T helper type 1 cytokines are considered key in keratinocyte injury. Compact orthokeratosis, wedge-shaped hypergranulosis, focal dyskeratosis, and colloid bodies typically are found on H&E staining, along with a dense bandlike lymphohistiocytic infiltrate at the dermoepidermal junction (DEJ)(Figure 3). Direct immunofluorescence typically shows a shaggy band of fibrinogen along the DEJ in addition to colloid bodies that stain with various autoantibodies including IgM, IgG, IgA, and C3.¹⁶

Bullous LP is a rare variant of LP that commonly develops on the oral mucosa and the legs, with blisters confined on pre-existing LP lesions.⁹ The pathogenesis is related to an epidermal inflammatory infiltrate that leads to basal layer destruction followed by dermal-epidermal separations that cause blistering.¹⁷ Bullous LP does not have positive DIF, IIF, or ELISA because the pathophysiology does not involve autoantibody production. Histopathology typically displays an extensive inflammatory infiltrate and degeneration of the basal keratinocytes, resulting in large dermal-epidermal separations called Max-Joseph spaces (Figure 4).¹⁷ Colloid bodies are prominent in bullous LP but rarely are seen in LPP; eosinophils also are much more prominent in LPP compared to bullous LP.¹⁸ Unlike in LPP, DIF usually is negative in bullous LP, though lichenoid lesions may exhibit globular deposition of IgM, IgG, and IgA in the colloid bodies of the lower epidermis and/or papillary dermis. Similar to LP, DIF of the biopsy specimen shows linear or shaggy deposits of fibrinogen at the DEJ.¹⁷

The Diagnosis: Lichen Planus Pemphigoides

Lichen planus pemphigoides (LPP) is a rare acquired autoimmune blistering disorder with an estimated worldwide prevalence of approximately 1 in 1,000,000 individuals.¹ It often manifests with overlapping features of both LP and bullous pemphigoid (BP). The condition usually presents in the fifth decade of life and has a slight female predominance.² Although primarily idiopathic, it has been associated with certain medications and treatments, such as angiotensin-converting enzyme inhibitors, programmed cell death protein 1 inhibitors, programmed cell death ligand 1 inhibitors, labetalol, narrowband UVB, and psoralen plus UVA.^3,4

Patients initially present with lesions of classic lichen planus (LP) with pink-purple, flat-topped, pruritic, polygonal papules and plaques.⁵ After weeks to months, tense vesicles and bullae usually develop on the sites of LP as well as on uninvolved skin. One study found a mean lag time of about 8.3 months for blistering to present after LP,⁵ but concurrent presentations of both have been reported.¹ In addition, oral mucosal involvement has been seen in 36% of cases. The most commonly affected sites are the extremities; however, involvement can be widespread.²

The pathogenesis of LPP currently is unknown. It has been proposed that in LP, injury of basal keratinocytes exposes hidden basement membrane and hemidesmosome antigens including BP180, a 180 kDa transmembrane protein of the basement membrane zone (BMZ),⁶ which triggers an immune response where T cells recognize the extracellular portion of BP180 and antibodies are formed against the likely autoantigen.1 One study has suggested that the autoantigen in LPP is the MCW-4 epitope within the C-terminal end of the NC16A domain of BP180.⁷

Histopathology of LPP reveals characteristics of both LP as well as BP. Typical features of LP on hematoxylin and eosin (H&E) staining include lichenoid lymphocytic interface dermatitis, sawtooth rete ridges, wedge-shaped hypergranulosis, and colloid bodies, as demonstrated from the biopsy of our patient’s gluteal cleft lesion (quiz image 1), while the predominant feature of BP on H&E staining includes a subepidermal bulla with eosinophils.² Typically, direct immunofluorescence (DIF) shows linear deposits of IgG and/or C3 along the BMZ. Indirect immunofluorescence (IIF) often reveals IgG against the roof of the BMZ in a human split-skin substrate.¹ Antibodies against BP180 or uncommonly BP230 often are detected on enzyme-linked immunosorbent assay (ELISA). For our patient, IIF and ELISA tests were positive. Given the clinical presentation with recurrent oral and gluteal cleft erosions, histologic findings, and the results of our patient’s immunological testing, the diagnosis of LPP was made.

Topical steroids often are used to treat localized disease of LPP.8 Oral prednisone also may be given for widespread or unresponsive disease.⁹ Other treatments include azathioprine, mycophenolate mofetil, hydroxychloroquine, dapsone, tetracycline in combination with nicotinamide, acitretin, ustekinumab, baricitinib, and rituximab with intravenous immunoglobulin.^3,8,10-12 Any potential medication culprits should be discontinued.⁹ Patients with oral involvement may require a soft diet to avoid further mucosal insult.¹⁰ Additionally, providers should consider dentistry, ophthalmology, and/or otolaryngology referrals depending on disease severity.

Bullous pemphigoid, the most common autoimmune blistering disease, has an estimated incidence of 10 to 43 per million individuals per year.² Classically, it presents with tense bullae on the skin of the lower abdomen, thighs, groin, forearms, and axillae. Circulating antibodies against 2 BMZ proteins—BP180 and BP230—are important factors in BP pathogenesis.² Diagnosis of BP is based on clinical features, histologic findings, and immunological studies including DIF, IIF, and ELISA. An eosinophil-rich subepidermal split typically is seen on H&E staining (Figure 1).

Direct immunofluorescence displays linear IgG and/ or C3 staining at the BMZ. Indirect immunofluorescence on a human salt-split skin substrate commonly shows linear BMZ deposition on the roof of the blister.² Indirect immunofluorescence for IgG deposition on monkey esophagus substrate shows linear BMZ deposition. Antibodies against the NC16A domain of BP180 (NC16A-BP180) are dominant, but BP230 antibodies against BP230 also are detected with ELISA.² Further studies have indicated that the NC16A epitopes of BP180 that are targeted in BP are MCW-0-3,² different from the autoantigen MCW-4 that is targeted in LPP.⁷

Paraneoplastic pemphigus (PNP) is another diagnosis to consider. Patients with PNP initially present with oral findings—most commonly chronic, erosive, and painful mucositis—followed by cutaneous involvement, which varies from the development of bullae to the formation of plaques similar to those of LP.¹³ The latter, in combination with oral erosions, may appear clinically similar to LPP. The results of DIF in conjugation with IIF and ELISA may help to further differentiate these disorders. Direct immunofluorescence in PNP typically reveals positive intercellular and/or BMZ IgG and C3, while DIF in LPP reveals depositions along the BMZ alone. Indirect immunofluorescence performed on rat bladder epithelium is particularly useful, as binding of IgG to rat bladder epithelium is characteristic of PNP and not seen in other disorders.¹⁴ Lastly, patients with PNP may develop IgG antibodies to various antigens such as desmoplakin I, desmoplakin II, envoplakin, periplakin, BP230, desmoglein 1, and desmoglein 3, which would not be expected in LPP patients.¹⁵ Hematoxylin and eosin staining differs from LPP, primarily with the location of the blister being intraepidermal. Acantholysis with hemorrhagic bullae can be seen (Figure 2).

Classic LP is an inflammatory disorder that mainly affects adults, with an estimated incidence of less than 1%.¹⁶ The classic form presents with purple, flat-topped, pruritic, polygonal papules and plaques of varying size that often are characterized by Wickham striae. Lichen planus possesses a broad spectrum of subtypes involving different locations, though skin lesions usually are localized to the extremities. Despite an unknown etiology, activated T cells and T helper type 1 cytokines are considered key in keratinocyte injury. Compact orthokeratosis, wedge-shaped hypergranulosis, focal dyskeratosis, and colloid bodies typically are found on H&E staining, along with a dense bandlike lymphohistiocytic infiltrate at the dermoepidermal junction (DEJ)(Figure 3). Direct immunofluorescence typically shows a shaggy band of fibrinogen along the DEJ in addition to colloid bodies that stain with various autoantibodies including IgM, IgG, IgA, and C3.¹⁶

Bullous LP is a rare variant of LP that commonly develops on the oral mucosa and the legs, with blisters confined on pre-existing LP lesions.⁹ The pathogenesis is related to an epidermal inflammatory infiltrate that leads to basal layer destruction followed by dermal-epidermal separations that cause blistering.¹⁷ Bullous LP does not have positive DIF, IIF, or ELISA because the pathophysiology does not involve autoantibody production. Histopathology typically displays an extensive inflammatory infiltrate and degeneration of the basal keratinocytes, resulting in large dermal-epidermal separations called Max-Joseph spaces (Figure 4).¹⁷ Colloid bodies are prominent in bullous LP but rarely are seen in LPP; eosinophils also are much more prominent in LPP compared to bullous LP.¹⁸ Unlike in LPP, DIF usually is negative in bullous LP, though lichenoid lesions may exhibit globular deposition of IgM, IgG, and IgA in the colloid bodies of the lower epidermis and/or papillary dermis. Similar to LP, DIF of the biopsy specimen shows linear or shaggy deposits of fibrinogen at the DEJ.¹⁷

Frontal fibrosing alopecia (FFA) is a lymphocytic cicatricial alopecia that primarily affects postmenopausal women. Considered a subtype of lichen planopilaris (LPP), FFA is histologically identical but presents as symmetric frontotemporal hairline recession rather than the multifocal distribution typical of LPP (Figure 1). Patients also may experience symptoms such as itching, facial papules, and eyebrow loss. As a progressive and scarring alopecia, early management of FFA is necessary to prevent permanent hair loss; however, there still are no clear guidelines regarding the efficacy of different treatment options for FFA due to a lack of randomized controlled studies in the literature. Patients with skin of color (SOC) also may have varying responses to treatment, further complicating the establishment of any treatment algorithm. Furthermore, symptoms, clinical findings, and demographics of FFA have been observed to vary across different ethnicities, especially among Black individuals. We conducted a systematic review of the literature on FFA in Black patients, with an analysis of demographics, clinical findings, concomitant skin conditions, treatments given, and treatment responses.

Methods

A PubMed search of articles indexed for MEDLINE was conducted of studies investigating FFA in patients with SOC from January 1, 2000, through November 30, 2020, using the terms frontal fibrosing alopecia, ethnicity, African, Black, Asian, Indian, Hispanic, and Latino. Articles were included if they were available in English and discussed treatment and clinical outcomes of FFA in Black individuals. The reference lists of included studies also were reviewed. Articles were assessed for quality of evidence using a 4-point scale (1=well-designed randomized controlled trials; 2=controlled trials with limitations or well-designed cohort or case-control studies; 3=case series with or without intervention; 4=case reports). Variables related to study type, patient demographics, treatments, and clinical outcomes were recorded.

Results

Of the 69 search results, 8 studies—2 retrospective cohort studies, 3 case series, and 3 case reports—describing 51 Black individuals with FFA were included in our review (eTable). Of these, 49 (96.1%) were female and 2 (3.9%) were male. Of the 45 females with data available for menopausal status, 24 (53.3%) were premenopausal and 21 (46.7%) were postmenopausal; data were not available for 4 females. Patients identified as African or African American in 27 (52.9%) cases, South African in 19 (37.3%), Black in 3 (5.9%), Indian in 1 (2.0%), and Afro-Caribbean in 1 (2.0%). The average age of FFA onset was 43.8 years in females (raw data available in 24 patients) and 35 years in males (raw data available in 2 patients). A family history of hair loss was reported in 15.7% (8/51) of patients.

Involved areas of hair loss included the frontotemporal hairline (51/51 [100%]), eyebrows (32/51 [62.7%]), limbs (4/51 [7.8%]), occiput (4/51 [7.8%]), facial hair (2/51 [3.9%]), vertex scalp (1/51 [2.0%]), and eyelashes (1/51 [2.0%]). Patchy alopecia suggestive of LPP was reported in 2 (3.9%) patients.

Patients frequently presented with scalp pruritus (26/51 [51.0%]), perifollicular papules or pustules (9/51 [17.6%]), and perifollicular hyperpigmentation (9/51 [17.6%]). Other associated symptoms included perifollicular erythema (6/51 [11.8%]), scalp pain (5/51 [9.8%]), hyperkeratosis or flaking (3/51 [5.9%]), and facial papules (2/51 [3.9%]). Loss of follicular ostia, prominent follicular ostia, and the lonely hair sign (Figure 2) was described in 21 (41.2%), 5 (9.8%), and 15 (29.4%) of patients, respectively. Hairstyles that involve scalp traction (19/51 [37.3%]) and/or chemicals (28/51 [54.9%]), such as hair dye or chemical relaxers, commonly were reported in patients prior to the onset of FFA.

The most commonly reported dermatologic comorbidities included traction alopecia (17/51 [33.3%]), followed by lichen planus pigmentosus (LLPigm)(7/51 [13.7%]), LPP (2/51 [3.9%]), psoriasis (1/51 [2.0%]), and morphea (1/51 [2.0%]). Reported comorbid diseases included Sjögren syndrome (2/51 [3.9%]), hypothyroidism (2/51 [3.9%]), HIV (1/51 [2.0%]), and diabetes mellitus (1/51 [2.0%]).

Of available reports (n=32), the most common histologic findings included perifollicular fibrosis (23/32 [71.9%]), lichenoid lymphocytic inflammation (22/23 [95.7%]) primarily affecting the isthmus and infundibular areas of the follicles, and decreased follicular density (21/23 [91.3%]).

The average time interval from treatment initiation to treatment assessment in available reports (n=25) was 1.8 years (range, 0.5–2 years). Response to treatment included regrowth of hair in 5.9% (3/51) of patients, FFA stabilization in 39.2% (20/51), FFA progression in 51.0% (26/51), and not reported in 3.9% (2/51). Combination therapy was used in 84.3% (43/51) of patients, while monotherapy was used in 11.8% (6/51), and 3.9% (2/51) did not have any treatment reported. Response to treatment was highly variable among patients, as were the combinations of therapeutic agents used (Table). Regrowth of hair was rare, occurring in only 2 (100%) patients treated with oral prednisone plus hydroxychloroquine (HCQ) or chloroquine (CHQ), and in 1 (50.0%) patient treated with topical corticosteroids plus antifungal shampoo, while there was no response in the other patient treated with this combination.

Improvement in hair loss, defined as having at least slowed progression of FFA, was observed in 100% (2/2) of patients who had oral steroids as part of their treatment regimen, followed by 5-alpha-reductase inhibitors (5-ARIs)(finasteride and dutasteride; 62.5% [5/8]), intralesional steroids (57.1% [8/14]), HCQ/CHQ (42.9% [15/35]), topical steroids (41.5% [17/41]), antifungal shampoo (40.0% [2/5]), topical/oral minoxidil (36.0% [9/25]), and tacrolimus (33.3% [7/21]).

Comment

Frontal fibrosing alopecia is a progressive scarring alopecia and a clinical variant of LPP. First described in 1994 by Kossard,¹ it initially was thought to be a disease of postmenopausal White women. Although still most prevalent in White individuals, there has been a growing number of reports describing FFA in patients with SOC, including Black individuals.¹⁰ Despite the increasing number of cases over the years, studies on the treatment of FFA remain sparse. Without expert guidelines, treatments usually are chosen based on clinician preferences. Few observational studies on these treatment modalities and their clinical outcomes exist, and the cohorts largely are composed of White patients.^10-12 However, Black individuals may respond differently to these treatments, just as they have been shown to exhibit unique features of FFA.³

Demographics of Patients With FFA—Consistent with our findings, prior studies have found that Black patients are more likely to be younger and premenopausal at FFA onset than their White counterparts.^13-15 Among the Black individuals included in our review, the majority were premenopausal (53%) with an average age of FFA onset of 46.7 years. Conversely, only 5% of 60 White females with FFA reported in a retrospective review were premenopausal and had an older mean age of FFA onset of 64 years,¹ substantiating prior reports.

Clinical Findings in Patients With FFA—The clinical findings observed in our cohort were consistent with what has previously been described in Black patients, including loss of follicular ostia (41.2%), lonely hair sign (29.4%), perifollicular erythema (11.8%), perifollicular papules (17.6%), and hyperkeratosis or flaking (5.9%). In comparing these findings with a review of 932 patients, 86% of whom were White, the observed frequencies of follicular ostia loss (38.3%) and lonely hair sign (26.7%) were similar; however, perifollicular erythema (44.2%), and hyperkeratosis (44.4%) were more prevalent in this group, while perifollicular papules (6.2%) were less common compared to our Black cohort.¹⁶ An explanation for this discrepancy in perifollicular erythema may be the increased skin pigmentation diminishing the appearance of erythema in Black individuals. Our cohort of Black individuals noted the presence of follicular hyperpigmentation (17.6%) and a high prevalence of scalp pruritus (51.0%), which appear to be more common in Black patients.^3,17 Although it is unclear why these differences in FFA presentation exist, it may be helpful for clinicians to be aware of these unique features when examining Black patients with suspected FFA.

Concomitant Cutaneous Disorders—A notable proportion of our cohort also had concomitant traction alopecia, which presents with frontotemporal alopecia, similar to FFA, making the diagnosis more challenging; however, the presence of perifollicular hyperpigmentation and facial hyperpigmentation in FFA may aid in differentiating these 2 entities.³ Other concomitant conditions noted in our review included androgenic alopecia, Sjögren syndrome, psoriasis, hypothyroidism, morphea, and HIV, suggesting a potential interplay between autoimmune, genetic, hormonal, and environmental components in the etiology of FFA. In fact, a recent study found that a persistent inflammatory response, loss of immune privilege, and a genetic susceptibility are some of the key processes in the pathogenesis of FFA.¹⁸ Although the authors speculated that there may be other triggers in initiating the onset of FFA, such as steroid hormones, sun exposure, and topical allergens, more evidence and controlled studies are needed

Additionally, concomitant LPPigm occurred in 13.7% of our FFA cohort, which appears to be more common in patients with darker skin types.^5,19-21 Lichen planus pigmentosus is a rare variant of LPP, and previous reports suggest that it may be associated with FFA.⁵ Similar to FFA, the pathogenesis of LPPigm also is unclear, and its treatment may be just as difficult.²² Because LPPigm may occur before, during, or after onset of FFA,²³ it may be helpful for clinicians to search for the signs of LPPigm in patients with darker skin types patients presenting with hair loss both as a diagnostic clue and so that treatment may be tailored to both conditions.

Response to Treatment—Similar to the varying clinical pictures, the response to treatment also can vary between patients of different ethnicities. For Black patients, treatment outcomes did not seem as successful as they did for other patients with SOC described in the literature. A retrospective cohort of 58 Asian individuals with FFA found that up to 90% had improvement or stabilization of FFA after treatment,²³ while only 45.1% (23/51) of the Black patients included in our study had improvement or stabilization. One reason may be that a greater proportion of Black patients are premenopausal at FFA onset (53%) compared to what is reported in Asian patients (28%),²³ and women who are premenopausal at FFA onset often face more severe disease.¹⁵ Although there may be additional explanations for these differences in treatment outcomes between ethnic groups, further investigation is needed.

All patients included in our study received either monotherapy or combination therapy of topical/intralesional/oral steroids, HCQ or CHQ, 5-ARIs, topical/oral minoxidil, antifungal shampoo, and/or a calcineurin inhibitor; however, most patients (51.0%) did not see a response to treatment, while only 45.1% showed slowed or halted progression of FFA. Hair regrowth was rare, occurring in only 3 (5.9%) patients; 2 of them were the only patients treated with oral prednisone, making for a potentially promising therapeutic for Black patients that should be further investigated in larger controlled cohort studies. In a prior study, intramuscular steroids (40 mg every 3 weeks) plus topical minoxidil were unsuccessful in slowing the progression of FFA in 3 postmenopausal women,²⁴ which may be explained by the racial differences in the response to FFA treatments and perhaps also menopausal status. Although not included in any of the regimens in our review, isotretinoin was shown to be effective in an ethnically unspecified group of patients (n=16) and also may be efficacious in Black individuals.²⁵ Although FFA may stabilize with time,²⁶ this was not observed in any of the patients included in our study; however, we only included patients who were treated, making it impossible to discern whether resolution was idiopathic or due to treatment.

Future Research—Research on treatments for FFA is lacking, especially in patients with SOC. Although we observed that there may be differences in the treatment response among Black individuals compared to other patients with SOC, additional studies are needed to delineate these racial differences, which can help guide management. More randomized controlled trials evaluating the various treatment regimens also are required to establish treatment guidelines. Frontal fibrosing alopecia likely is underdiagnosed in Black individuals, contributing to the lack of research in this group. Darker skin can obscure some of the clinical and dermoscopic features that are more visible in fair skin. Furthermore, it may be challenging to distinguish clinical features of FFA in the setting of concomitant traction alopecia, which is more common in Black patients.²⁷ Frontal fibrosing alopecia presenting in Black women also is less likely to be biopsied, contributing to the tendency to miss FFA in favor of traction or androgenic alopecia, which often are assumed to be more common in this population.^2,27 Therefore, histologic evaluation through biopsy is paramount in securing an accurate diagnosis for Black patients with frontotemporal alopecia.

Study Limitations—The studies included in our review were limited by a lack of control comparison groups, especially among the retrospective cohort studies. Additionally, some of the studies included cases refractory to prior treatment modalities, possibly leading to a selection bias of more severe cases that were not representative of FFA in the general population. Thus, further studies involving larger populations of those with SOC are needed to fully evaluate the clinical utility of the current treatment modalities in this group.

Frontal fibrosing alopecia (FFA) is a lymphocytic cicatricial alopecia that primarily affects postmenopausal women. Considered a subtype of lichen planopilaris (LPP), FFA is histologically identical but presents as symmetric frontotemporal hairline recession rather than the multifocal distribution typical of LPP (Figure 1). Patients also may experience symptoms such as itching, facial papules, and eyebrow loss. As a progressive and scarring alopecia, early management of FFA is necessary to prevent permanent hair loss; however, there still are no clear guidelines regarding the efficacy of different treatment options for FFA due to a lack of randomized controlled studies in the literature. Patients with skin of color (SOC) also may have varying responses to treatment, further complicating the establishment of any treatment algorithm. Furthermore, symptoms, clinical findings, and demographics of FFA have been observed to vary across different ethnicities, especially among Black individuals. We conducted a systematic review of the literature on FFA in Black patients, with an analysis of demographics, clinical findings, concomitant skin conditions, treatments given, and treatment responses.

Methods

A PubMed search of articles indexed for MEDLINE was conducted of studies investigating FFA in patients with SOC from January 1, 2000, through November 30, 2020, using the terms frontal fibrosing alopecia, ethnicity, African, Black, Asian, Indian, Hispanic, and Latino. Articles were included if they were available in English and discussed treatment and clinical outcomes of FFA in Black individuals. The reference lists of included studies also were reviewed. Articles were assessed for quality of evidence using a 4-point scale (1=well-designed randomized controlled trials; 2=controlled trials with limitations or well-designed cohort or case-control studies; 3=case series with or without intervention; 4=case reports). Variables related to study type, patient demographics, treatments, and clinical outcomes were recorded.

Results

Of the 69 search results, 8 studies—2 retrospective cohort studies, 3 case series, and 3 case reports—describing 51 Black individuals with FFA were included in our review (eTable). Of these, 49 (96.1%) were female and 2 (3.9%) were male. Of the 45 females with data available for menopausal status, 24 (53.3%) were premenopausal and 21 (46.7%) were postmenopausal; data were not available for 4 females. Patients identified as African or African American in 27 (52.9%) cases, South African in 19 (37.3%), Black in 3 (5.9%), Indian in 1 (2.0%), and Afro-Caribbean in 1 (2.0%). The average age of FFA onset was 43.8 years in females (raw data available in 24 patients) and 35 years in males (raw data available in 2 patients). A family history of hair loss was reported in 15.7% (8/51) of patients.

Involved areas of hair loss included the frontotemporal hairline (51/51 [100%]), eyebrows (32/51 [62.7%]), limbs (4/51 [7.8%]), occiput (4/51 [7.8%]), facial hair (2/51 [3.9%]), vertex scalp (1/51 [2.0%]), and eyelashes (1/51 [2.0%]). Patchy alopecia suggestive of LPP was reported in 2 (3.9%) patients.

Patients frequently presented with scalp pruritus (26/51 [51.0%]), perifollicular papules or pustules (9/51 [17.6%]), and perifollicular hyperpigmentation (9/51 [17.6%]). Other associated symptoms included perifollicular erythema (6/51 [11.8%]), scalp pain (5/51 [9.8%]), hyperkeratosis or flaking (3/51 [5.9%]), and facial papules (2/51 [3.9%]). Loss of follicular ostia, prominent follicular ostia, and the lonely hair sign (Figure 2) was described in 21 (41.2%), 5 (9.8%), and 15 (29.4%) of patients, respectively. Hairstyles that involve scalp traction (19/51 [37.3%]) and/or chemicals (28/51 [54.9%]), such as hair dye or chemical relaxers, commonly were reported in patients prior to the onset of FFA.

The most commonly reported dermatologic comorbidities included traction alopecia (17/51 [33.3%]), followed by lichen planus pigmentosus (LLPigm)(7/51 [13.7%]), LPP (2/51 [3.9%]), psoriasis (1/51 [2.0%]), and morphea (1/51 [2.0%]). Reported comorbid diseases included Sjögren syndrome (2/51 [3.9%]), hypothyroidism (2/51 [3.9%]), HIV (1/51 [2.0%]), and diabetes mellitus (1/51 [2.0%]).

Of available reports (n=32), the most common histologic findings included perifollicular fibrosis (23/32 [71.9%]), lichenoid lymphocytic inflammation (22/23 [95.7%]) primarily affecting the isthmus and infundibular areas of the follicles, and decreased follicular density (21/23 [91.3%]).

The average time interval from treatment initiation to treatment assessment in available reports (n=25) was 1.8 years (range, 0.5–2 years). Response to treatment included regrowth of hair in 5.9% (3/51) of patients, FFA stabilization in 39.2% (20/51), FFA progression in 51.0% (26/51), and not reported in 3.9% (2/51). Combination therapy was used in 84.3% (43/51) of patients, while monotherapy was used in 11.8% (6/51), and 3.9% (2/51) did not have any treatment reported. Response to treatment was highly variable among patients, as were the combinations of therapeutic agents used (Table). Regrowth of hair was rare, occurring in only 2 (100%) patients treated with oral prednisone plus hydroxychloroquine (HCQ) or chloroquine (CHQ), and in 1 (50.0%) patient treated with topical corticosteroids plus antifungal shampoo, while there was no response in the other patient treated with this combination.

Improvement in hair loss, defined as having at least slowed progression of FFA, was observed in 100% (2/2) of patients who had oral steroids as part of their treatment regimen, followed by 5-alpha-reductase inhibitors (5-ARIs)(finasteride and dutasteride; 62.5% [5/8]), intralesional steroids (57.1% [8/14]), HCQ/CHQ (42.9% [15/35]), topical steroids (41.5% [17/41]), antifungal shampoo (40.0% [2/5]), topical/oral minoxidil (36.0% [9/25]), and tacrolimus (33.3% [7/21]).

Comment

Frontal fibrosing alopecia is a progressive scarring alopecia and a clinical variant of LPP. First described in 1994 by Kossard,¹ it initially was thought to be a disease of postmenopausal White women. Although still most prevalent in White individuals, there has been a growing number of reports describing FFA in patients with SOC, including Black individuals.¹⁰ Despite the increasing number of cases over the years, studies on the treatment of FFA remain sparse. Without expert guidelines, treatments usually are chosen based on clinician preferences. Few observational studies on these treatment modalities and their clinical outcomes exist, and the cohorts largely are composed of White patients.^10-12 However, Black individuals may respond differently to these treatments, just as they have been shown to exhibit unique features of FFA.³

Demographics of Patients With FFA—Consistent with our findings, prior studies have found that Black patients are more likely to be younger and premenopausal at FFA onset than their White counterparts.^13-15 Among the Black individuals included in our review, the majority were premenopausal (53%) with an average age of FFA onset of 46.7 years. Conversely, only 5% of 60 White females with FFA reported in a retrospective review were premenopausal and had an older mean age of FFA onset of 64 years,¹ substantiating prior reports.

Clinical Findings in Patients With FFA—The clinical findings observed in our cohort were consistent with what has previously been described in Black patients, including loss of follicular ostia (41.2%), lonely hair sign (29.4%), perifollicular erythema (11.8%), perifollicular papules (17.6%), and hyperkeratosis or flaking (5.9%). In comparing these findings with a review of 932 patients, 86% of whom were White, the observed frequencies of follicular ostia loss (38.3%) and lonely hair sign (26.7%) were similar; however, perifollicular erythema (44.2%), and hyperkeratosis (44.4%) were more prevalent in this group, while perifollicular papules (6.2%) were less common compared to our Black cohort.¹⁶ An explanation for this discrepancy in perifollicular erythema may be the increased skin pigmentation diminishing the appearance of erythema in Black individuals. Our cohort of Black individuals noted the presence of follicular hyperpigmentation (17.6%) and a high prevalence of scalp pruritus (51.0%), which appear to be more common in Black patients.^3,17 Although it is unclear why these differences in FFA presentation exist, it may be helpful for clinicians to be aware of these unique features when examining Black patients with suspected FFA.

Concomitant Cutaneous Disorders—A notable proportion of our cohort also had concomitant traction alopecia, which presents with frontotemporal alopecia, similar to FFA, making the diagnosis more challenging; however, the presence of perifollicular hyperpigmentation and facial hyperpigmentation in FFA may aid in differentiating these 2 entities.³ Other concomitant conditions noted in our review included androgenic alopecia, Sjögren syndrome, psoriasis, hypothyroidism, morphea, and HIV, suggesting a potential interplay between autoimmune, genetic, hormonal, and environmental components in the etiology of FFA. In fact, a recent study found that a persistent inflammatory response, loss of immune privilege, and a genetic susceptibility are some of the key processes in the pathogenesis of FFA.¹⁸ Although the authors speculated that there may be other triggers in initiating the onset of FFA, such as steroid hormones, sun exposure, and topical allergens, more evidence and controlled studies are needed

Additionally, concomitant LPPigm occurred in 13.7% of our FFA cohort, which appears to be more common in patients with darker skin types.^5,19-21 Lichen planus pigmentosus is a rare variant of LPP, and previous reports suggest that it may be associated with FFA.⁵ Similar to FFA, the pathogenesis of LPPigm also is unclear, and its treatment may be just as difficult.²² Because LPPigm may occur before, during, or after onset of FFA,²³ it may be helpful for clinicians to search for the signs of LPPigm in patients with darker skin types patients presenting with hair loss both as a diagnostic clue and so that treatment may be tailored to both conditions.

Response to Treatment—Similar to the varying clinical pictures, the response to treatment also can vary between patients of different ethnicities. For Black patients, treatment outcomes did not seem as successful as they did for other patients with SOC described in the literature. A retrospective cohort of 58 Asian individuals with FFA found that up to 90% had improvement or stabilization of FFA after treatment,²³ while only 45.1% (23/51) of the Black patients included in our study had improvement or stabilization. One reason may be that a greater proportion of Black patients are premenopausal at FFA onset (53%) compared to what is reported in Asian patients (28%),²³ and women who are premenopausal at FFA onset often face more severe disease.¹⁵ Although there may be additional explanations for these differences in treatment outcomes between ethnic groups, further investigation is needed.

All patients included in our study received either monotherapy or combination therapy of topical/intralesional/oral steroids, HCQ or CHQ, 5-ARIs, topical/oral minoxidil, antifungal shampoo, and/or a calcineurin inhibitor; however, most patients (51.0%) did not see a response to treatment, while only 45.1% showed slowed or halted progression of FFA. Hair regrowth was rare, occurring in only 3 (5.9%) patients; 2 of them were the only patients treated with oral prednisone, making for a potentially promising therapeutic for Black patients that should be further investigated in larger controlled cohort studies. In a prior study, intramuscular steroids (40 mg every 3 weeks) plus topical minoxidil were unsuccessful in slowing the progression of FFA in 3 postmenopausal women,²⁴ which may be explained by the racial differences in the response to FFA treatments and perhaps also menopausal status. Although not included in any of the regimens in our review, isotretinoin was shown to be effective in an ethnically unspecified group of patients (n=16) and also may be efficacious in Black individuals.²⁵ Although FFA may stabilize with time,²⁶ this was not observed in any of the patients included in our study; however, we only included patients who were treated, making it impossible to discern whether resolution was idiopathic or due to treatment.

Future Research—Research on treatments for FFA is lacking, especially in patients with SOC. Although we observed that there may be differences in the treatment response among Black individuals compared to other patients with SOC, additional studies are needed to delineate these racial differences, which can help guide management. More randomized controlled trials evaluating the various treatment regimens also are required to establish treatment guidelines. Frontal fibrosing alopecia likely is underdiagnosed in Black individuals, contributing to the lack of research in this group. Darker skin can obscure some of the clinical and dermoscopic features that are more visible in fair skin. Furthermore, it may be challenging to distinguish clinical features of FFA in the setting of concomitant traction alopecia, which is more common in Black patients.²⁷ Frontal fibrosing alopecia presenting in Black women also is less likely to be biopsied, contributing to the tendency to miss FFA in favor of traction or androgenic alopecia, which often are assumed to be more common in this population.^2,27 Therefore, histologic evaluation through biopsy is paramount in securing an accurate diagnosis for Black patients with frontotemporal alopecia.

Study Limitations—The studies included in our review were limited by a lack of control comparison groups, especially among the retrospective cohort studies. Additionally, some of the studies included cases refractory to prior treatment modalities, possibly leading to a selection bias of more severe cases that were not representative of FFA in the general population. Thus, further studies involving larger populations of those with SOC are needed to fully evaluate the clinical utility of the current treatment modalities in this group.

Frontal fibrosing alopecia (FFA) is a lymphocytic cicatricial alopecia that primarily affects postmenopausal women. Considered a subtype of lichen planopilaris (LPP), FFA is histologically identical but presents as symmetric frontotemporal hairline recession rather than the multifocal distribution typical of LPP (Figure 1). Patients also may experience symptoms such as itching, facial papules, and eyebrow loss. As a progressive and scarring alopecia, early management of FFA is necessary to prevent permanent hair loss; however, there still are no clear guidelines regarding the efficacy of different treatment options for FFA due to a lack of randomized controlled studies in the literature. Patients with skin of color (SOC) also may have varying responses to treatment, further complicating the establishment of any treatment algorithm. Furthermore, symptoms, clinical findings, and demographics of FFA have been observed to vary across different ethnicities, especially among Black individuals. We conducted a systematic review of the literature on FFA in Black patients, with an analysis of demographics, clinical findings, concomitant skin conditions, treatments given, and treatment responses.

Methods

A PubMed search of articles indexed for MEDLINE was conducted of studies investigating FFA in patients with SOC from January 1, 2000, through November 30, 2020, using the terms frontal fibrosing alopecia, ethnicity, African, Black, Asian, Indian, Hispanic, and Latino. Articles were included if they were available in English and discussed treatment and clinical outcomes of FFA in Black individuals. The reference lists of included studies also were reviewed. Articles were assessed for quality of evidence using a 4-point scale (1=well-designed randomized controlled trials; 2=controlled trials with limitations or well-designed cohort or case-control studies; 3=case series with or without intervention; 4=case reports). Variables related to study type, patient demographics, treatments, and clinical outcomes were recorded.

Results

Of the 69 search results, 8 studies—2 retrospective cohort studies, 3 case series, and 3 case reports—describing 51 Black individuals with FFA were included in our review (eTable). Of these, 49 (96.1%) were female and 2 (3.9%) were male. Of the 45 females with data available for menopausal status, 24 (53.3%) were premenopausal and 21 (46.7%) were postmenopausal; data were not available for 4 females. Patients identified as African or African American in 27 (52.9%) cases, South African in 19 (37.3%), Black in 3 (5.9%), Indian in 1 (2.0%), and Afro-Caribbean in 1 (2.0%). The average age of FFA onset was 43.8 years in females (raw data available in 24 patients) and 35 years in males (raw data available in 2 patients). A family history of hair loss was reported in 15.7% (8/51) of patients.

Involved areas of hair loss included the frontotemporal hairline (51/51 [100%]), eyebrows (32/51 [62.7%]), limbs (4/51 [7.8%]), occiput (4/51 [7.8%]), facial hair (2/51 [3.9%]), vertex scalp (1/51 [2.0%]), and eyelashes (1/51 [2.0%]). Patchy alopecia suggestive of LPP was reported in 2 (3.9%) patients.

Patients frequently presented with scalp pruritus (26/51 [51.0%]), perifollicular papules or pustules (9/51 [17.6%]), and perifollicular hyperpigmentation (9/51 [17.6%]). Other associated symptoms included perifollicular erythema (6/51 [11.8%]), scalp pain (5/51 [9.8%]), hyperkeratosis or flaking (3/51 [5.9%]), and facial papules (2/51 [3.9%]). Loss of follicular ostia, prominent follicular ostia, and the lonely hair sign (Figure 2) was described in 21 (41.2%), 5 (9.8%), and 15 (29.4%) of patients, respectively. Hairstyles that involve scalp traction (19/51 [37.3%]) and/or chemicals (28/51 [54.9%]), such as hair dye or chemical relaxers, commonly were reported in patients prior to the onset of FFA.

The most commonly reported dermatologic comorbidities included traction alopecia (17/51 [33.3%]), followed by lichen planus pigmentosus (LLPigm)(7/51 [13.7%]), LPP (2/51 [3.9%]), psoriasis (1/51 [2.0%]), and morphea (1/51 [2.0%]). Reported comorbid diseases included Sjögren syndrome (2/51 [3.9%]), hypothyroidism (2/51 [3.9%]), HIV (1/51 [2.0%]), and diabetes mellitus (1/51 [2.0%]).

Of available reports (n=32), the most common histologic findings included perifollicular fibrosis (23/32 [71.9%]), lichenoid lymphocytic inflammation (22/23 [95.7%]) primarily affecting the isthmus and infundibular areas of the follicles, and decreased follicular density (21/23 [91.3%]).

The average time interval from treatment initiation to treatment assessment in available reports (n=25) was 1.8 years (range, 0.5–2 years). Response to treatment included regrowth of hair in 5.9% (3/51) of patients, FFA stabilization in 39.2% (20/51), FFA progression in 51.0% (26/51), and not reported in 3.9% (2/51). Combination therapy was used in 84.3% (43/51) of patients, while monotherapy was used in 11.8% (6/51), and 3.9% (2/51) did not have any treatment reported. Response to treatment was highly variable among patients, as were the combinations of therapeutic agents used (Table). Regrowth of hair was rare, occurring in only 2 (100%) patients treated with oral prednisone plus hydroxychloroquine (HCQ) or chloroquine (CHQ), and in 1 (50.0%) patient treated with topical corticosteroids plus antifungal shampoo, while there was no response in the other patient treated with this combination.

Improvement in hair loss, defined as having at least slowed progression of FFA, was observed in 100% (2/2) of patients who had oral steroids as part of their treatment regimen, followed by 5-alpha-reductase inhibitors (5-ARIs)(finasteride and dutasteride; 62.5% [5/8]), intralesional steroids (57.1% [8/14]), HCQ/CHQ (42.9% [15/35]), topical steroids (41.5% [17/41]), antifungal shampoo (40.0% [2/5]), topical/oral minoxidil (36.0% [9/25]), and tacrolimus (33.3% [7/21]).

Comment

Frontal fibrosing alopecia is a progressive scarring alopecia and a clinical variant of LPP. First described in 1994 by Kossard,¹ it initially was thought to be a disease of postmenopausal White women. Although still most prevalent in White individuals, there has been a growing number of reports describing FFA in patients with SOC, including Black individuals.¹⁰ Despite the increasing number of cases over the years, studies on the treatment of FFA remain sparse. Without expert guidelines, treatments usually are chosen based on clinician preferences. Few observational studies on these treatment modalities and their clinical outcomes exist, and the cohorts largely are composed of White patients.^10-12 However, Black individuals may respond differently to these treatments, just as they have been shown to exhibit unique features of FFA.³

Demographics of Patients With FFA—Consistent with our findings, prior studies have found that Black patients are more likely to be younger and premenopausal at FFA onset than their White counterparts.^13-15 Among the Black individuals included in our review, the majority were premenopausal (53%) with an average age of FFA onset of 46.7 years. Conversely, only 5% of 60 White females with FFA reported in a retrospective review were premenopausal and had an older mean age of FFA onset of 64 years,¹ substantiating prior reports.

Clinical Findings in Patients With FFA—The clinical findings observed in our cohort were consistent with what has previously been described in Black patients, including loss of follicular ostia (41.2%), lonely hair sign (29.4%), perifollicular erythema (11.8%), perifollicular papules (17.6%), and hyperkeratosis or flaking (5.9%). In comparing these findings with a review of 932 patients, 86% of whom were White, the observed frequencies of follicular ostia loss (38.3%) and lonely hair sign (26.7%) were similar; however, perifollicular erythema (44.2%), and hyperkeratosis (44.4%) were more prevalent in this group, while perifollicular papules (6.2%) were less common compared to our Black cohort.¹⁶ An explanation for this discrepancy in perifollicular erythema may be the increased skin pigmentation diminishing the appearance of erythema in Black individuals. Our cohort of Black individuals noted the presence of follicular hyperpigmentation (17.6%) and a high prevalence of scalp pruritus (51.0%), which appear to be more common in Black patients.^3,17 Although it is unclear why these differences in FFA presentation exist, it may be helpful for clinicians to be aware of these unique features when examining Black patients with suspected FFA.

Concomitant Cutaneous Disorders—A notable proportion of our cohort also had concomitant traction alopecia, which presents with frontotemporal alopecia, similar to FFA, making the diagnosis more challenging; however, the presence of perifollicular hyperpigmentation and facial hyperpigmentation in FFA may aid in differentiating these 2 entities.³ Other concomitant conditions noted in our review included androgenic alopecia, Sjögren syndrome, psoriasis, hypothyroidism, morphea, and HIV, suggesting a potential interplay between autoimmune, genetic, hormonal, and environmental components in the etiology of FFA. In fact, a recent study found that a persistent inflammatory response, loss of immune privilege, and a genetic susceptibility are some of the key processes in the pathogenesis of FFA.¹⁸ Although the authors speculated that there may be other triggers in initiating the onset of FFA, such as steroid hormones, sun exposure, and topical allergens, more evidence and controlled studies are needed

Additionally, concomitant LPPigm occurred in 13.7% of our FFA cohort, which appears to be more common in patients with darker skin types.^5,19-21 Lichen planus pigmentosus is a rare variant of LPP, and previous reports suggest that it may be associated with FFA.⁵ Similar to FFA, the pathogenesis of LPPigm also is unclear, and its treatment may be just as difficult.²² Because LPPigm may occur before, during, or after onset of FFA,²³ it may be helpful for clinicians to search for the signs of LPPigm in patients with darker skin types patients presenting with hair loss both as a diagnostic clue and so that treatment may be tailored to both conditions.

Response to Treatment—Similar to the varying clinical pictures, the response to treatment also can vary between patients of different ethnicities. For Black patients, treatment outcomes did not seem as successful as they did for other patients with SOC described in the literature. A retrospective cohort of 58 Asian individuals with FFA found that up to 90% had improvement or stabilization of FFA after treatment,²³ while only 45.1% (23/51) of the Black patients included in our study had improvement or stabilization. One reason may be that a greater proportion of Black patients are premenopausal at FFA onset (53%) compared to what is reported in Asian patients (28%),²³ and women who are premenopausal at FFA onset often face more severe disease.¹⁵ Although there may be additional explanations for these differences in treatment outcomes between ethnic groups, further investigation is needed.

All patients included in our study received either monotherapy or combination therapy of topical/intralesional/oral steroids, HCQ or CHQ, 5-ARIs, topical/oral minoxidil, antifungal shampoo, and/or a calcineurin inhibitor; however, most patients (51.0%) did not see a response to treatment, while only 45.1% showed slowed or halted progression of FFA. Hair regrowth was rare, occurring in only 3 (5.9%) patients; 2 of them were the only patients treated with oral prednisone, making for a potentially promising therapeutic for Black patients that should be further investigated in larger controlled cohort studies. In a prior study, intramuscular steroids (40 mg every 3 weeks) plus topical minoxidil were unsuccessful in slowing the progression of FFA in 3 postmenopausal women,²⁴ which may be explained by the racial differences in the response to FFA treatments and perhaps also menopausal status. Although not included in any of the regimens in our review, isotretinoin was shown to be effective in an ethnically unspecified group of patients (n=16) and also may be efficacious in Black individuals.²⁵ Although FFA may stabilize with time,²⁶ this was not observed in any of the patients included in our study; however, we only included patients who were treated, making it impossible to discern whether resolution was idiopathic or due to treatment.

Future Research—Research on treatments for FFA is lacking, especially in patients with SOC. Although we observed that there may be differences in the treatment response among Black individuals compared to other patients with SOC, additional studies are needed to delineate these racial differences, which can help guide management. More randomized controlled trials evaluating the various treatment regimens also are required to establish treatment guidelines. Frontal fibrosing alopecia likely is underdiagnosed in Black individuals, contributing to the lack of research in this group. Darker skin can obscure some of the clinical and dermoscopic features that are more visible in fair skin. Furthermore, it may be challenging to distinguish clinical features of FFA in the setting of concomitant traction alopecia, which is more common in Black patients.²⁷ Frontal fibrosing alopecia presenting in Black women also is less likely to be biopsied, contributing to the tendency to miss FFA in favor of traction or androgenic alopecia, which often are assumed to be more common in this population.^2,27 Therefore, histologic evaluation through biopsy is paramount in securing an accurate diagnosis for Black patients with frontotemporal alopecia.

Study Limitations—The studies included in our review were limited by a lack of control comparison groups, especially among the retrospective cohort studies. Additionally, some of the studies included cases refractory to prior treatment modalities, possibly leading to a selection bias of more severe cases that were not representative of FFA in the general population. Thus, further studies involving larger populations of those with SOC are needed to fully evaluate the clinical utility of the current treatment modalities in this group.

Laundry detergent, a cleaning agent ubiquitous in the modern household, often is suspected as a cause of allergic contact dermatitis (ACD). In one North American study, 10.7% of 738 patients undergoing patch testing believed that laundry detergent was a contributing factor, whereas their referring physicians had the same concern less often (in 2.3% of cases).¹Likewise, in a 1992 survey of western US households, more than 20% of 3841 respondents reported skin or health problems attributed to a textile and/or laundry product.² The suspicion of laundry detergent as a causative agent of ACD is perpetuated across popular wellness and beauty websites.^3,4 Does the evidence support this degree of suspicion? Or, similar to the well-meaning parent who misguidedly fixates on foods as the cause of their child’s atopic dermatitis and believes elimination diets are the solution,⁵ could a similar desire for control in the face of the unpredictability of eczema drive consumers and health care providers alike to blame laundry detergent—a familiar and modifiable cause?

We provide a summary of the evidence for the potential allergenicity of laundry detergent, including common allergens present in laundry detergent, the role of machine washing, and the differential diagnosis for laundry detergent–associated ACD.

Allergenic Ingredients in Laundry Detergent

Potential allergens present in laundry detergent include fragrances, preservatives, surfactants, emulsifiers, bleaches, brighteners, enzymes, and dyes.^6-8 In an analysis of allergens present in laundry detergents available in the United States, fragrances and preservatives were most common (eTable).^7,8 Contact allergy to fragrances occurs in approximately 3.5% of the general population⁹ and is detected in as many as 9.2% of patients referred for patch testing in North America.¹⁰ Preservatives commonly found in laundry detergent include isothiazolinones, such as methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI), MI alone, and benzisothiazolinone (BIT). Methylisothiazolinone has gained attention for causing an ACD epidemic beginning in the early 2000s and peaking in Europe between 2013 and 2014 and decreasing thereafter due to consumer personal care product regulatory changes enacted in the European Union.¹¹ In contrast, rates of MI allergy in North America have continued to increase (reaching as high as 15% of patch tested patients in 2017-2018) due to a lack of similar regulation.^10,12 More recently, the prevalence of positive patch tests to BIT has been rising, though it often is difficult to ascertain relevant sources of exposure, and some cases could represent cross-reactions to MCI/MI.^10,13

Other allergens that may be present in laundry detergent include surfactants and propylene glycol. Alkyl glucosides such as decyl glucoside and lauryl glucoside are considered gentle surfactants and often are included in products marketed as safe for sensitive skin,¹⁴ such as “free and gentle” detergents.⁸ However, they actually may pose an increased risk for sensitization in patients with atopic dermatitis.¹⁴ In addition to being allergenic, surfactants and emulsifiers are known irritants.^6,15 Although pathologically distinct, ACD and irritant contact dermatitis can be indistinguishable on clinical presentation.

How Commonly Does Laundry Detergent Cause ACD?

The mere presence of a contact allergen in laundry detergent does not necessarily imply that it is likely to cause ACD. To do so, the chemical in question must exceed the exposure thresholds for primary sensitization (ie, induction of contact allergy) and/or elicitation (ie, development of ACD in sensitized individuals). These depend on a complex interplay of product- and patient-specific factors, among them the concentration of the chemical in the detergent, the method of use, and the amount of detergent residue remaining on clothing after washing.

In the 1990s, the North American Contact Dermatitis Group (NACDG) attempted to determine the prevalence of ACD caused by laundry detergent.¹ Among 738 patients patch tested to aqueous dilutions of granular and liquid laundry detergents, only 5 (0.7%) had a possible allergic patch test reaction. It was unclear what the culprit allergens in the detergents may have been; only 1 of the patients also tested positive to fragrance. Two patients underwent further testing to additional detergent dilutions, and the results called into question whether their initial reactions had truly been allergic (positive) or were actually irritant (negative). The investigators concluded that the prevalence of laundry detergent–associated ACD in this large group of patients was at most 0.7%, and possibly lower.¹

Importantly, patch testing to laundry detergents should not be undertaken in routine clinical practice. Laundry detergents should never be tested “as is” (ie, undiluted) on the skin; they are inherently irritating and have a high likelihood of producing misleading false-positive reactions. Careful dilutions and testing of control subjects are necessary if patch testing with these products is to be appropriately conducted.

The extremely low prevalence of laundry detergent–associated ACD reported by the NACDG was determined prior to the start of the worldwide MI allergy epidemic, raising the possibility that laundry detergents containing isothiazolinones may be associated with ACD. There is no consensus about the minimum level at which isothiazolinones pose no risk to consumers,^16-19 but the US Expert Panel for Cosmetic Ingredient Safety declared that MI is “safe for use in rinse-off cosmetic products at concentrations up to 100 ppm and safe in leave-on cosmetic products when they are formulated to be nonsensitizing.”^18,19 Although ingredient lists do not always reveal when isothiazolinones are present, analyses of commercially available laundry detergents have shown MI concentrations ranging from undetectable to 65.7 ppm.^20-23

Published reports suggest that MCI/MI in laundry detergent can elicit ACD in sensitized individuals. In one case, a 7-year-old girl with chronic truncal dermatitis (atopic history unspecified) was patch tested, revealing a strongly positive reaction to MCI/MI.²⁴ Her laundry detergent was the only personal product found to contain MI. The dermatitis completely resolved after switching detergents and flared after wearing a jacket that had been washed in the implicated detergent, further supporting the relevance of the positive patch test. The investigators suspected initial sensitization to MI from wet wipes used earlier in childhood.²⁴ In another case involving occupational exposure, a 39-year-old nonatopic factory worker was responsible for directly adding MI to laundry detergent.²⁵ Although he wore disposable work gloves, he developed severe hand dermatitis, eczematous pretibial patches, and generalized pruritus. Patch testing revealed positive reactions to MCI/MI and MI, and he experienced improvement when reassigned to different work duties. It was hypothesized that the leg dermatitis and generalized pruritus may have been related to exposure to small concentrations of MI in work clothes washed with an MI-containing detergent.²⁵ Notably, this patient’s level of exposure was much greater than that encountered by individuals in day-to-day life outside of specialized occupational settings.

Regarding other isothiazolinones, a toxicologic study estimated that BIT in laundry detergent would be unlikely to induce sensitization, even at the maximal acceptable concentration, as recommended by preservative manufacturers, and accounting for undiluted detergent spilling directly onto the skin.²⁶Nonetheless, a single European center recently reported that almost half of the 38 patients with positive patch tests to BIT had a potentially relevant exposure attributed to household cleaning products, including laundry detergent.¹³ This emphasizes the need for further examination of sources of exposure to this increasingly common positive patch test allergen.

Does Machine Washing Impact Allergen Concentrations?

Two recent investigations have suggested that machine washing reduces concentrations of isothiazolinones to levels that are likely below clinical relevance. In the first study, 3 fabrics—cotton, polyester, cotton-polyester—were machine washed and line dried.²⁷ A standard detergent was used with MI added at different concentrations: less than 1 ppm, 100 ppm, and 1000 ppm. This process was either performed once or 10 times. Following laundering and line drying, MI was undetectable in all fabrics regardless of MI concentration or number of times washed (detection limit, 0.5 ppm).²⁷ In the second study, 4 fabrics—cotton, wool, polyester, linen—were washed with standard laundry detergent in 1 of 4 ways: handwashing (positive control), standard machine washing, standard machine washing with fabric softener, and standard machine washing with a double rinse.²⁸ After laundering and line drying, concentrations of MI, MCI, and BIT were low or undetectable regardless of fabric type or method of laundering. The highest levels detected were in handwashed garments at a maximum of 0.5 ppm of MI. The study authors postulated that chemical concentrations near these maximum residual levels may pose a risk for eliciting ACD in highly sensitized individuals. Therefore, handwashing can be considered a much higher risk activity for isothiazolinone ACD compared with machine washing.²⁸

It is intriguing that machine washing appears to reduce isothiazolinones to low concentrations that may have limited likelihood of causing ACD. Similar findings have been reported regarding fragrances. A quantitative risk assessment performed on 24 of 26 fragrance allergens regulated by the European Union determined that the amount of fragrance deposited on the skin from laundered garments would be less than the threshold for causing sensitization.²⁹ Although this risk assessment was unable to address the threshold of elicitation, another study conducted in Europe investigated whether fragrance residues present on fabric, such as those deposited from laundry detergent, are present at high enough concentrations to elicit ACD in previously sensitized individuals.³⁰ When 36 individuals were patch tested with increasing concentrations of a fragrance to which they were already sensitized, only 2 (5.6%) had a weakly positive reaction and then only to the highest concentration, which was estimated to be 20-fold higher than the level of skin exposure after normal laundering. No patient reacted at lower concentrations.³⁰

Although machine washing may decrease isothiazolinone and/or fragrance concentrations in laundry detergent to below clinically relevant levels, these findings should not necessarily be extrapolated to all chemicals in laundry detergent. Indeed, a prior study observed that after washing cotton cloths in a detergent solution for 10 minutes, detergent residue was present at concentrations ranging from 139 to 2820 ppm and required a subsequent 20 to 22 washes in water to become undetectable.³¹ Another study produced a mathematical model of the residual concentration of sodium dodecyl sulphate (SDS), a surfactant and known irritant, in laundered clothing.³² It was estimated that after machine washing, the residual concentration of SDS on clothes would be too low to cause irritation; however, as the clothes dry (ie, as moisture evaporates but solutes remain), the concentration of SDS on the fabric’s surface would increase to potentially irritating levels. The extensive drying that is possible with electric dryers may further enhance this solute-concentrating effect.

Differential Diagnosis of Laundry Detergent ACD

The propensity for laundry detergent to cause ACD is a question that is nowhere near settled, but the prevalence of allergy likely is far less common than is generally suspected. In our experience, many patients presenting for patch testing have already made the change to “free and clear” detergents without noticeable improvement in their dermatitis, which could possibly relate to the ongoing presence of contact allergens in these “gentle” formulations.⁷ However, to avoid anchoring bias, more frequent causes of dermatitis should be included in the differential diagnosis. Textile ACD presents beneath clothing with accentuation at areas of closest contact with the skin, classically involving the axillary rim but sparing the vault. The most frequently implicated allergens in textile ACD are disperse dyes and less commonly textile resins.^33,34 Between 2017 and 2018, 2.3% of 4882 patients patch tested by the NACDG reacted positively to disperse dye mix.¹⁰ There is evidence to suggest that the actual prevalence of disperse dye allergy might be higher due to inadequacy of screening allergens on baseline patch test series.³⁵ Additional diagnoses that should be distinguished from presumed detergent contact dermatitis include atopic dermatitis and cutaneous T-cell lymphoma.

Final Interpretation

Although many patients and physicians consider laundry detergent to be a major cause of ACD, there is limited high-quality evidence to support this belief. Contact allergy to laundry detergent is probably much less common than is widely supposed. Although laundry detergents can contain common allergens such as fragrances and preservatives, evidence suggests that they are likely reduced to below clinically relevant levels during routine machine washing; however, we cannot assume that we are in the “free and clear,” as uncertainty remains about the impact of these low concentrationson individuals with strong contact allergy, and large studies of patch testing to modern detergents have yet to be carried out.

Laundry detergent, a cleaning agent ubiquitous in the modern household, often is suspected as a cause of allergic contact dermatitis (ACD). In one North American study, 10.7% of 738 patients undergoing patch testing believed that laundry detergent was a contributing factor, whereas their referring physicians had the same concern less often (in 2.3% of cases).¹Likewise, in a 1992 survey of western US households, more than 20% of 3841 respondents reported skin or health problems attributed to a textile and/or laundry product.² The suspicion of laundry detergent as a causative agent of ACD is perpetuated across popular wellness and beauty websites.^3,4 Does the evidence support this degree of suspicion? Or, similar to the well-meaning parent who misguidedly fixates on foods as the cause of their child’s atopic dermatitis and believes elimination diets are the solution,⁵ could a similar desire for control in the face of the unpredictability of eczema drive consumers and health care providers alike to blame laundry detergent—a familiar and modifiable cause?

We provide a summary of the evidence for the potential allergenicity of laundry detergent, including common allergens present in laundry detergent, the role of machine washing, and the differential diagnosis for laundry detergent–associated ACD.

Allergenic Ingredients in Laundry Detergent

Potential allergens present in laundry detergent include fragrances, preservatives, surfactants, emulsifiers, bleaches, brighteners, enzymes, and dyes.^6-8 In an analysis of allergens present in laundry detergents available in the United States, fragrances and preservatives were most common (eTable).^7,8 Contact allergy to fragrances occurs in approximately 3.5% of the general population⁹ and is detected in as many as 9.2% of patients referred for patch testing in North America.¹⁰ Preservatives commonly found in laundry detergent include isothiazolinones, such as methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI), MI alone, and benzisothiazolinone (BIT). Methylisothiazolinone has gained attention for causing an ACD epidemic beginning in the early 2000s and peaking in Europe between 2013 and 2014 and decreasing thereafter due to consumer personal care product regulatory changes enacted in the European Union.¹¹ In contrast, rates of MI allergy in North America have continued to increase (reaching as high as 15% of patch tested patients in 2017-2018) due to a lack of similar regulation.^10,12 More recently, the prevalence of positive patch tests to BIT has been rising, though it often is difficult to ascertain relevant sources of exposure, and some cases could represent cross-reactions to MCI/MI.^10,13

Other allergens that may be present in laundry detergent include surfactants and propylene glycol. Alkyl glucosides such as decyl glucoside and lauryl glucoside are considered gentle surfactants and often are included in products marketed as safe for sensitive skin,¹⁴ such as “free and gentle” detergents.⁸ However, they actually may pose an increased risk for sensitization in patients with atopic dermatitis.¹⁴ In addition to being allergenic, surfactants and emulsifiers are known irritants.^6,15 Although pathologically distinct, ACD and irritant contact dermatitis can be indistinguishable on clinical presentation.

How Commonly Does Laundry Detergent Cause ACD?

The mere presence of a contact allergen in laundry detergent does not necessarily imply that it is likely to cause ACD. To do so, the chemical in question must exceed the exposure thresholds for primary sensitization (ie, induction of contact allergy) and/or elicitation (ie, development of ACD in sensitized individuals). These depend on a complex interplay of product- and patient-specific factors, among them the concentration of the chemical in the detergent, the method of use, and the amount of detergent residue remaining on clothing after washing.

In the 1990s, the North American Contact Dermatitis Group (NACDG) attempted to determine the prevalence of ACD caused by laundry detergent.¹ Among 738 patients patch tested to aqueous dilutions of granular and liquid laundry detergents, only 5 (0.7%) had a possible allergic patch test reaction. It was unclear what the culprit allergens in the detergents may have been; only 1 of the patients also tested positive to fragrance. Two patients underwent further testing to additional detergent dilutions, and the results called into question whether their initial reactions had truly been allergic (positive) or were actually irritant (negative). The investigators concluded that the prevalence of laundry detergent–associated ACD in this large group of patients was at most 0.7%, and possibly lower.¹

Importantly, patch testing to laundry detergents should not be undertaken in routine clinical practice. Laundry detergents should never be tested “as is” (ie, undiluted) on the skin; they are inherently irritating and have a high likelihood of producing misleading false-positive reactions. Careful dilutions and testing of control subjects are necessary if patch testing with these products is to be appropriately conducted.

The extremely low prevalence of laundry detergent–associated ACD reported by the NACDG was determined prior to the start of the worldwide MI allergy epidemic, raising the possibility that laundry detergents containing isothiazolinones may be associated with ACD. There is no consensus about the minimum level at which isothiazolinones pose no risk to consumers,^16-19 but the US Expert Panel for Cosmetic Ingredient Safety declared that MI is “safe for use in rinse-off cosmetic products at concentrations up to 100 ppm and safe in leave-on cosmetic products when they are formulated to be nonsensitizing.”^18,19 Although ingredient lists do not always reveal when isothiazolinones are present, analyses of commercially available laundry detergents have shown MI concentrations ranging from undetectable to 65.7 ppm.^20-23

Published reports suggest that MCI/MI in laundry detergent can elicit ACD in sensitized individuals. In one case, a 7-year-old girl with chronic truncal dermatitis (atopic history unspecified) was patch tested, revealing a strongly positive reaction to MCI/MI.²⁴ Her laundry detergent was the only personal product found to contain MI. The dermatitis completely resolved after switching detergents and flared after wearing a jacket that had been washed in the implicated detergent, further supporting the relevance of the positive patch test. The investigators suspected initial sensitization to MI from wet wipes used earlier in childhood.²⁴ In another case involving occupational exposure, a 39-year-old nonatopic factory worker was responsible for directly adding MI to laundry detergent.²⁵ Although he wore disposable work gloves, he developed severe hand dermatitis, eczematous pretibial patches, and generalized pruritus. Patch testing revealed positive reactions to MCI/MI and MI, and he experienced improvement when reassigned to different work duties. It was hypothesized that the leg dermatitis and generalized pruritus may have been related to exposure to small concentrations of MI in work clothes washed with an MI-containing detergent.²⁵ Notably, this patient’s level of exposure was much greater than that encountered by individuals in day-to-day life outside of specialized occupational settings.

Regarding other isothiazolinones, a toxicologic study estimated that BIT in laundry detergent would be unlikely to induce sensitization, even at the maximal acceptable concentration, as recommended by preservative manufacturers, and accounting for undiluted detergent spilling directly onto the skin.²⁶Nonetheless, a single European center recently reported that almost half of the 38 patients with positive patch tests to BIT had a potentially relevant exposure attributed to household cleaning products, including laundry detergent.¹³ This emphasizes the need for further examination of sources of exposure to this increasingly common positive patch test allergen.

Does Machine Washing Impact Allergen Concentrations?

Two recent investigations have suggested that machine washing reduces concentrations of isothiazolinones to levels that are likely below clinical relevance. In the first study, 3 fabrics—cotton, polyester, cotton-polyester—were machine washed and line dried.²⁷ A standard detergent was used with MI added at different concentrations: less than 1 ppm, 100 ppm, and 1000 ppm. This process was either performed once or 10 times. Following laundering and line drying, MI was undetectable in all fabrics regardless of MI concentration or number of times washed (detection limit, 0.5 ppm).²⁷ In the second study, 4 fabrics—cotton, wool, polyester, linen—were washed with standard laundry detergent in 1 of 4 ways: handwashing (positive control), standard machine washing, standard machine washing with fabric softener, and standard machine washing with a double rinse.²⁸ After laundering and line drying, concentrations of MI, MCI, and BIT were low or undetectable regardless of fabric type or method of laundering. The highest levels detected were in handwashed garments at a maximum of 0.5 ppm of MI. The study authors postulated that chemical concentrations near these maximum residual levels may pose a risk for eliciting ACD in highly sensitized individuals. Therefore, handwashing can be considered a much higher risk activity for isothiazolinone ACD compared with machine washing.²⁸

It is intriguing that machine washing appears to reduce isothiazolinones to low concentrations that may have limited likelihood of causing ACD. Similar findings have been reported regarding fragrances. A quantitative risk assessment performed on 24 of 26 fragrance allergens regulated by the European Union determined that the amount of fragrance deposited on the skin from laundered garments would be less than the threshold for causing sensitization.²⁹ Although this risk assessment was unable to address the threshold of elicitation, another study conducted in Europe investigated whether fragrance residues present on fabric, such as those deposited from laundry detergent, are present at high enough concentrations to elicit ACD in previously sensitized individuals.³⁰ When 36 individuals were patch tested with increasing concentrations of a fragrance to which they were already sensitized, only 2 (5.6%) had a weakly positive reaction and then only to the highest concentration, which was estimated to be 20-fold higher than the level of skin exposure after normal laundering. No patient reacted at lower concentrations.³⁰

Although machine washing may decrease isothiazolinone and/or fragrance concentrations in laundry detergent to below clinically relevant levels, these findings should not necessarily be extrapolated to all chemicals in laundry detergent. Indeed, a prior study observed that after washing cotton cloths in a detergent solution for 10 minutes, detergent residue was present at concentrations ranging from 139 to 2820 ppm and required a subsequent 20 to 22 washes in water to become undetectable.³¹ Another study produced a mathematical model of the residual concentration of sodium dodecyl sulphate (SDS), a surfactant and known irritant, in laundered clothing.³² It was estimated that after machine washing, the residual concentration of SDS on clothes would be too low to cause irritation; however, as the clothes dry (ie, as moisture evaporates but solutes remain), the concentration of SDS on the fabric’s surface would increase to potentially irritating levels. The extensive drying that is possible with electric dryers may further enhance this solute-concentrating effect.

Differential Diagnosis of Laundry Detergent ACD

The propensity for laundry detergent to cause ACD is a question that is nowhere near settled, but the prevalence of allergy likely is far less common than is generally suspected. In our experience, many patients presenting for patch testing have already made the change to “free and clear” detergents without noticeable improvement in their dermatitis, which could possibly relate to the ongoing presence of contact allergens in these “gentle” formulations.⁷ However, to avoid anchoring bias, more frequent causes of dermatitis should be included in the differential diagnosis. Textile ACD presents beneath clothing with accentuation at areas of closest contact with the skin, classically involving the axillary rim but sparing the vault. The most frequently implicated allergens in textile ACD are disperse dyes and less commonly textile resins.^33,34 Between 2017 and 2018, 2.3% of 4882 patients patch tested by the NACDG reacted positively to disperse dye mix.¹⁰ There is evidence to suggest that the actual prevalence of disperse dye allergy might be higher due to inadequacy of screening allergens on baseline patch test series.³⁵ Additional diagnoses that should be distinguished from presumed detergent contact dermatitis include atopic dermatitis and cutaneous T-cell lymphoma.

Final Interpretation

Although many patients and physicians consider laundry detergent to be a major cause of ACD, there is limited high-quality evidence to support this belief. Contact allergy to laundry detergent is probably much less common than is widely supposed. Although laundry detergents can contain common allergens such as fragrances and preservatives, evidence suggests that they are likely reduced to below clinically relevant levels during routine machine washing; however, we cannot assume that we are in the “free and clear,” as uncertainty remains about the impact of these low concentrationson individuals with strong contact allergy, and large studies of patch testing to modern detergents have yet to be carried out.

Laundry detergent, a cleaning agent ubiquitous in the modern household, often is suspected as a cause of allergic contact dermatitis (ACD). In one North American study, 10.7% of 738 patients undergoing patch testing believed that laundry detergent was a contributing factor, whereas their referring physicians had the same concern less often (in 2.3% of cases).¹Likewise, in a 1992 survey of western US households, more than 20% of 3841 respondents reported skin or health problems attributed to a textile and/or laundry product.² The suspicion of laundry detergent as a causative agent of ACD is perpetuated across popular wellness and beauty websites.^3,4 Does the evidence support this degree of suspicion? Or, similar to the well-meaning parent who misguidedly fixates on foods as the cause of their child’s atopic dermatitis and believes elimination diets are the solution,⁵ could a similar desire for control in the face of the unpredictability of eczema drive consumers and health care providers alike to blame laundry detergent—a familiar and modifiable cause?

We provide a summary of the evidence for the potential allergenicity of laundry detergent, including common allergens present in laundry detergent, the role of machine washing, and the differential diagnosis for laundry detergent–associated ACD.

Allergenic Ingredients in Laundry Detergent

Potential allergens present in laundry detergent include fragrances, preservatives, surfactants, emulsifiers, bleaches, brighteners, enzymes, and dyes.^6-8 In an analysis of allergens present in laundry detergents available in the United States, fragrances and preservatives were most common (eTable).^7,8 Contact allergy to fragrances occurs in approximately 3.5% of the general population⁹ and is detected in as many as 9.2% of patients referred for patch testing in North America.¹⁰ Preservatives commonly found in laundry detergent include isothiazolinones, such as methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI), MI alone, and benzisothiazolinone (BIT). Methylisothiazolinone has gained attention for causing an ACD epidemic beginning in the early 2000s and peaking in Europe between 2013 and 2014 and decreasing thereafter due to consumer personal care product regulatory changes enacted in the European Union.¹¹ In contrast, rates of MI allergy in North America have continued to increase (reaching as high as 15% of patch tested patients in 2017-2018) due to a lack of similar regulation.^10,12 More recently, the prevalence of positive patch tests to BIT has been rising, though it often is difficult to ascertain relevant sources of exposure, and some cases could represent cross-reactions to MCI/MI.^10,13

Other allergens that may be present in laundry detergent include surfactants and propylene glycol. Alkyl glucosides such as decyl glucoside and lauryl glucoside are considered gentle surfactants and often are included in products marketed as safe for sensitive skin,¹⁴ such as “free and gentle” detergents.⁸ However, they actually may pose an increased risk for sensitization in patients with atopic dermatitis.¹⁴ In addition to being allergenic, surfactants and emulsifiers are known irritants.^6,15 Although pathologically distinct, ACD and irritant contact dermatitis can be indistinguishable on clinical presentation.

How Commonly Does Laundry Detergent Cause ACD?

The mere presence of a contact allergen in laundry detergent does not necessarily imply that it is likely to cause ACD. To do so, the chemical in question must exceed the exposure thresholds for primary sensitization (ie, induction of contact allergy) and/or elicitation (ie, development of ACD in sensitized individuals). These depend on a complex interplay of product- and patient-specific factors, among them the concentration of the chemical in the detergent, the method of use, and the amount of detergent residue remaining on clothing after washing.

In the 1990s, the North American Contact Dermatitis Group (NACDG) attempted to determine the prevalence of ACD caused by laundry detergent.¹ Among 738 patients patch tested to aqueous dilutions of granular and liquid laundry detergents, only 5 (0.7%) had a possible allergic patch test reaction. It was unclear what the culprit allergens in the detergents may have been; only 1 of the patients also tested positive to fragrance. Two patients underwent further testing to additional detergent dilutions, and the results called into question whether their initial reactions had truly been allergic (positive) or were actually irritant (negative). The investigators concluded that the prevalence of laundry detergent–associated ACD in this large group of patients was at most 0.7%, and possibly lower.¹

Importantly, patch testing to laundry detergents should not be undertaken in routine clinical practice. Laundry detergents should never be tested “as is” (ie, undiluted) on the skin; they are inherently irritating and have a high likelihood of producing misleading false-positive reactions. Careful dilutions and testing of control subjects are necessary if patch testing with these products is to be appropriately conducted.

The extremely low prevalence of laundry detergent–associated ACD reported by the NACDG was determined prior to the start of the worldwide MI allergy epidemic, raising the possibility that laundry detergents containing isothiazolinones may be associated with ACD. There is no consensus about the minimum level at which isothiazolinones pose no risk to consumers,^16-19 but the US Expert Panel for Cosmetic Ingredient Safety declared that MI is “safe for use in rinse-off cosmetic products at concentrations up to 100 ppm and safe in leave-on cosmetic products when they are formulated to be nonsensitizing.”^18,19 Although ingredient lists do not always reveal when isothiazolinones are present, analyses of commercially available laundry detergents have shown MI concentrations ranging from undetectable to 65.7 ppm.^20-23

Published reports suggest that MCI/MI in laundry detergent can elicit ACD in sensitized individuals. In one case, a 7-year-old girl with chronic truncal dermatitis (atopic history unspecified) was patch tested, revealing a strongly positive reaction to MCI/MI.²⁴ Her laundry detergent was the only personal product found to contain MI. The dermatitis completely resolved after switching detergents and flared after wearing a jacket that had been washed in the implicated detergent, further supporting the relevance of the positive patch test. The investigators suspected initial sensitization to MI from wet wipes used earlier in childhood.²⁴ In another case involving occupational exposure, a 39-year-old nonatopic factory worker was responsible for directly adding MI to laundry detergent.²⁵ Although he wore disposable work gloves, he developed severe hand dermatitis, eczematous pretibial patches, and generalized pruritus. Patch testing revealed positive reactions to MCI/MI and MI, and he experienced improvement when reassigned to different work duties. It was hypothesized that the leg dermatitis and generalized pruritus may have been related to exposure to small concentrations of MI in work clothes washed with an MI-containing detergent.²⁵ Notably, this patient’s level of exposure was much greater than that encountered by individuals in day-to-day life outside of specialized occupational settings.

Regarding other isothiazolinones, a toxicologic study estimated that BIT in laundry detergent would be unlikely to induce sensitization, even at the maximal acceptable concentration, as recommended by preservative manufacturers, and accounting for undiluted detergent spilling directly onto the skin.²⁶Nonetheless, a single European center recently reported that almost half of the 38 patients with positive patch tests to BIT had a potentially relevant exposure attributed to household cleaning products, including laundry detergent.¹³ This emphasizes the need for further examination of sources of exposure to this increasingly common positive patch test allergen.

Does Machine Washing Impact Allergen Concentrations?

Two recent investigations have suggested that machine washing reduces concentrations of isothiazolinones to levels that are likely below clinical relevance. In the first study, 3 fabrics—cotton, polyester, cotton-polyester—were machine washed and line dried.²⁷ A standard detergent was used with MI added at different concentrations: less than 1 ppm, 100 ppm, and 1000 ppm. This process was either performed once or 10 times. Following laundering and line drying, MI was undetectable in all fabrics regardless of MI concentration or number of times washed (detection limit, 0.5 ppm).²⁷ In the second study, 4 fabrics—cotton, wool, polyester, linen—were washed with standard laundry detergent in 1 of 4 ways: handwashing (positive control), standard machine washing, standard machine washing with fabric softener, and standard machine washing with a double rinse.²⁸ After laundering and line drying, concentrations of MI, MCI, and BIT were low or undetectable regardless of fabric type or method of laundering. The highest levels detected were in handwashed garments at a maximum of 0.5 ppm of MI. The study authors postulated that chemical concentrations near these maximum residual levels may pose a risk for eliciting ACD in highly sensitized individuals. Therefore, handwashing can be considered a much higher risk activity for isothiazolinone ACD compared with machine washing.²⁸

It is intriguing that machine washing appears to reduce isothiazolinones to low concentrations that may have limited likelihood of causing ACD. Similar findings have been reported regarding fragrances. A quantitative risk assessment performed on 24 of 26 fragrance allergens regulated by the European Union determined that the amount of fragrance deposited on the skin from laundered garments would be less than the threshold for causing sensitization.²⁹ Although this risk assessment was unable to address the threshold of elicitation, another study conducted in Europe investigated whether fragrance residues present on fabric, such as those deposited from laundry detergent, are present at high enough concentrations to elicit ACD in previously sensitized individuals.³⁰ When 36 individuals were patch tested with increasing concentrations of a fragrance to which they were already sensitized, only 2 (5.6%) had a weakly positive reaction and then only to the highest concentration, which was estimated to be 20-fold higher than the level of skin exposure after normal laundering. No patient reacted at lower concentrations.³⁰

Although machine washing may decrease isothiazolinone and/or fragrance concentrations in laundry detergent to below clinically relevant levels, these findings should not necessarily be extrapolated to all chemicals in laundry detergent. Indeed, a prior study observed that after washing cotton cloths in a detergent solution for 10 minutes, detergent residue was present at concentrations ranging from 139 to 2820 ppm and required a subsequent 20 to 22 washes in water to become undetectable.³¹ Another study produced a mathematical model of the residual concentration of sodium dodecyl sulphate (SDS), a surfactant and known irritant, in laundered clothing.³² It was estimated that after machine washing, the residual concentration of SDS on clothes would be too low to cause irritation; however, as the clothes dry (ie, as moisture evaporates but solutes remain), the concentration of SDS on the fabric’s surface would increase to potentially irritating levels. The extensive drying that is possible with electric dryers may further enhance this solute-concentrating effect.

Differential Diagnosis of Laundry Detergent ACD

The propensity for laundry detergent to cause ACD is a question that is nowhere near settled, but the prevalence of allergy likely is far less common than is generally suspected. In our experience, many patients presenting for patch testing have already made the change to “free and clear” detergents without noticeable improvement in their dermatitis, which could possibly relate to the ongoing presence of contact allergens in these “gentle” formulations.⁷ However, to avoid anchoring bias, more frequent causes of dermatitis should be included in the differential diagnosis. Textile ACD presents beneath clothing with accentuation at areas of closest contact with the skin, classically involving the axillary rim but sparing the vault. The most frequently implicated allergens in textile ACD are disperse dyes and less commonly textile resins.^33,34 Between 2017 and 2018, 2.3% of 4882 patients patch tested by the NACDG reacted positively to disperse dye mix.¹⁰ There is evidence to suggest that the actual prevalence of disperse dye allergy might be higher due to inadequacy of screening allergens on baseline patch test series.³⁵ Additional diagnoses that should be distinguished from presumed detergent contact dermatitis include atopic dermatitis and cutaneous T-cell lymphoma.

Final Interpretation

Although many patients and physicians consider laundry detergent to be a major cause of ACD, there is limited high-quality evidence to support this belief. Contact allergy to laundry detergent is probably much less common than is widely supposed. Although laundry detergents can contain common allergens such as fragrances and preservatives, evidence suggests that they are likely reduced to below clinically relevant levels during routine machine washing; however, we cannot assume that we are in the “free and clear,” as uncertainty remains about the impact of these low concentrationson individuals with strong contact allergy, and large studies of patch testing to modern detergents have yet to be carried out.

The 2022 mpox (monkeypox) virus outbreak represents the latest example of how infectious diseases with previously limited reach can spread in a globalized society. More than 86,000 cases have been reported worldwide, with more than 30,000 cases in the United States as of March 15, 2023.¹ Herein, we summarize the key features of mpox infection for the dermatologist.

Mpox Transmission

The mpox virus is a double-stranded DNA virus of the Orthopoxvirus genus and Poxviridae family.^2,3 There are 2 types of the mpox virus: clade I (formerly the Congo Basin clade) and clade II (formerly the West African clade). Clade I causes more severe disease (10% mortality rate), while clade II is associated with lower mortality (1%–3%) and has been split into subclades of IIa (exhibits zoonotic transmission) and IIb (exhibits human-to-human spread).^3,4 The current outbreak is caused by clade IIb, and patients typically have no travel history to classic endemic regions.^5,6

In endemic countries, mpox transmission is zoonotic from small forest animals. In nonendemic countries, sporadic cases rarely have been reported, including a cluster in the United States in 2003 related to pet prairie dogs. In stark contrast, human-to-human transmission is occurring in the current epidemic mainly via intimate skin-to-skin contact and possibly via sexual fluids, meeting the criteria for a sexually transmitted infection. However, nonsexual transmission does still occur, though it is less common.⁷ Many of the reported cases so far are in young to middle-aged men who have sex with men (MSM).^2,8 However, it is crucial to understand that mpox is not exclusive to the MSM population; the virus has been transmitted to heterosexual males, females, children, and even household pets of infected individuals.^2,9,10 Labeling mpox as exclusive to the MSM community is both inaccurate and inappropriately stigmatizing.

Cutaneous Presentation and Diagnosis of Mpox

Mpox has an incubation time of approximately 9 days (range, 7–21 days), after which affected persons develop macular lesions that evolve over 2 to 4 weeks into papules, vesicles, and deep-seated pustules before crusting over and resolving with possible residual scarring.^{2,3,5,9,11,12} Palmoplantar involvement is a key feature.¹¹ Although in some cases there will be multiple lesions with centrifugal progression, the lesions also may be few in number, with some patients presenting with a single lesion in the anogenital region or on the face, hand, or foot (Figure).^6,9 Systemic symptoms such as prodromal fever, lymphadenopathy, and headache are common but not universal.^9,13 Potential complications include penile edema, proctitis, bacterial superinfection, tonsillitis, conjunctivitis, encephalitis, and pneumonia.^5,9,13

Images used with permission from Roneet Lev, MD (San Diego, California), and VisualDx.

A high index of suspicion is needed to diagnose mpox infection. The differential diagnosis includes smallpox; varicella-zoster virus (primary or reactivation); secondary syphilis; measles; herpes simplex virus; molluscum contagiosum; hand, foot, and mouth disease; and disseminated gonococcal infection.^2,3 For lesions confined to the genital area, sexually transmitted infections (eg, chancroid, lymphogranuloma venereum) as well as non–sexually related acute genital ulcers (Lipschütz ulcers) should be considered.²

Certain clinical features may help in distinguishing mpox from other diseases. Mpox exhibits synchronous progression and centrifugal distribution when multiple lesions are present; in contrast, the lesions of primary varicella (chickenpox) appear in multiple different stages, and those of localized herpes zoster (shingles) exhibit a dermatomal distribution. When these features are present, mpox causes a greater degree of lymphadenopathy and systemic symptoms than primary varicella.³Clinical diagnosis of mpox is more than 90% sensitive but only 9% to 26% specific.³ To confirm the diagnosis, a viral swab vigorously obtained from active skin lesions should be sent in viral transport media for mpox DNA-specific polymerase chain reaction testing, which is available from major laboratories.^2,3 Other supportive tests include serum studies for anti–mpox virus immunoglobulins and immunohistochemical staining for viral antigens on skin biopsy specimens.² When evaluating suspected and confirmed mpox cases, dermatologists should wear a gown, gloves, a fitted N95 mask, and eye protection to prevent infection.⁵

Treating Mpox

Symptomatic mpox infection can last for up to 2 to 5 weeks.³ The patient is no longer infectious once the lesions have crusted over.^3,11 The majority of cases require supportive care only.^2,3,5,14 However, mpox remains a potentially fatal disease, with 38 deaths to date in the current outbreak.¹ High-risk populations include children younger than 8 years, pregnant women, and individuals who are immunocompromised.¹⁵ Tecovirimat, an antiviral medication approved by the US Food and Drug Administration (FDA) for smallpox, is available via the expanded access Investigational New Drug (EA-IND) protocol to treat severe mpox cases but is not widely available in the United States.^6,16-18 Brincidofovir, a prodrug of the antiviral cidofovir, possesses single-patient emergency use Investigational New Drug (e-IND) status for treatment of mpox but also is not widely available in the United States.¹⁷ Intravenous vaccinia immune globulin is under consideration for high-risk individuals, but little is known regarding its efficacy against mpox.^5,16,17

Two smallpox vaccines—JYNNEOS (Bavarian Nordic) and ACAM2000 (Emergent Bio Solutions)—are available for both preexposure and postexposure prophylaxis against mpox virus.¹⁹ At this time, only JYNNEOS is FDA approved for the prevention of mpox; ACAM2000 can be used against mpox under the FDA’s EA-IND protocol, which involves additional requirements, including informed consent from the patient.²⁰ ACAM2000 is a live, replication-competent vaccine that carries a warning of increased risk for side effects in patients with cardiac disease, pregnancy, immunocompromise, and a history or presence of eczema and other skin conditions.^3,21,22 JYNNEOS is a live but replication-deficient virus and therefore does not carry these warnings.^3,21,22

Final Thoughts

Mpox is no longer an obscure illness occurring in limited geographic areas. Dermatologists must remain highly vigilant when evaluating any patient for new-onset vesicular or pustular eruptions to combat this ongoing public health threat. This issue of Cutis^® also features a thorough mpox update on the clinical presentation, vaccine guidance, and management.²³

The 2022 mpox (monkeypox) virus outbreak represents the latest example of how infectious diseases with previously limited reach can spread in a globalized society. More than 86,000 cases have been reported worldwide, with more than 30,000 cases in the United States as of March 15, 2023.¹ Herein, we summarize the key features of mpox infection for the dermatologist.

Mpox Transmission

The mpox virus is a double-stranded DNA virus of the Orthopoxvirus genus and Poxviridae family.^2,3 There are 2 types of the mpox virus: clade I (formerly the Congo Basin clade) and clade II (formerly the West African clade). Clade I causes more severe disease (10% mortality rate), while clade II is associated with lower mortality (1%–3%) and has been split into subclades of IIa (exhibits zoonotic transmission) and IIb (exhibits human-to-human spread).^3,4 The current outbreak is caused by clade IIb, and patients typically have no travel history to classic endemic regions.^5,6

In endemic countries, mpox transmission is zoonotic from small forest animals. In nonendemic countries, sporadic cases rarely have been reported, including a cluster in the United States in 2003 related to pet prairie dogs. In stark contrast, human-to-human transmission is occurring in the current epidemic mainly via intimate skin-to-skin contact and possibly via sexual fluids, meeting the criteria for a sexually transmitted infection. However, nonsexual transmission does still occur, though it is less common.⁷ Many of the reported cases so far are in young to middle-aged men who have sex with men (MSM).^2,8 However, it is crucial to understand that mpox is not exclusive to the MSM population; the virus has been transmitted to heterosexual males, females, children, and even household pets of infected individuals.^2,9,10 Labeling mpox as exclusive to the MSM community is both inaccurate and inappropriately stigmatizing.

Cutaneous Presentation and Diagnosis of Mpox

Mpox has an incubation time of approximately 9 days (range, 7–21 days), after which affected persons develop macular lesions that evolve over 2 to 4 weeks into papules, vesicles, and deep-seated pustules before crusting over and resolving with possible residual scarring.^{2,3,5,9,11,12} Palmoplantar involvement is a key feature.¹¹ Although in some cases there will be multiple lesions with centrifugal progression, the lesions also may be few in number, with some patients presenting with a single lesion in the anogenital region or on the face, hand, or foot (Figure).^6,9 Systemic symptoms such as prodromal fever, lymphadenopathy, and headache are common but not universal.^9,13 Potential complications include penile edema, proctitis, bacterial superinfection, tonsillitis, conjunctivitis, encephalitis, and pneumonia.^5,9,13

Images used with permission from Roneet Lev, MD (San Diego, California), and VisualDx.

A high index of suspicion is needed to diagnose mpox infection. The differential diagnosis includes smallpox; varicella-zoster virus (primary or reactivation); secondary syphilis; measles; herpes simplex virus; molluscum contagiosum; hand, foot, and mouth disease; and disseminated gonococcal infection.^2,3 For lesions confined to the genital area, sexually transmitted infections (eg, chancroid, lymphogranuloma venereum) as well as non–sexually related acute genital ulcers (Lipschütz ulcers) should be considered.²

Certain clinical features may help in distinguishing mpox from other diseases. Mpox exhibits synchronous progression and centrifugal distribution when multiple lesions are present; in contrast, the lesions of primary varicella (chickenpox) appear in multiple different stages, and those of localized herpes zoster (shingles) exhibit a dermatomal distribution. When these features are present, mpox causes a greater degree of lymphadenopathy and systemic symptoms than primary varicella.³Clinical diagnosis of mpox is more than 90% sensitive but only 9% to 26% specific.³ To confirm the diagnosis, a viral swab vigorously obtained from active skin lesions should be sent in viral transport media for mpox DNA-specific polymerase chain reaction testing, which is available from major laboratories.^2,3 Other supportive tests include serum studies for anti–mpox virus immunoglobulins and immunohistochemical staining for viral antigens on skin biopsy specimens.² When evaluating suspected and confirmed mpox cases, dermatologists should wear a gown, gloves, a fitted N95 mask, and eye protection to prevent infection.⁵

Treating Mpox

Symptomatic mpox infection can last for up to 2 to 5 weeks.³ The patient is no longer infectious once the lesions have crusted over.^3,11 The majority of cases require supportive care only.^2,3,5,14 However, mpox remains a potentially fatal disease, with 38 deaths to date in the current outbreak.¹ High-risk populations include children younger than 8 years, pregnant women, and individuals who are immunocompromised.¹⁵ Tecovirimat, an antiviral medication approved by the US Food and Drug Administration (FDA) for smallpox, is available via the expanded access Investigational New Drug (EA-IND) protocol to treat severe mpox cases but is not widely available in the United States.^6,16-18 Brincidofovir, a prodrug of the antiviral cidofovir, possesses single-patient emergency use Investigational New Drug (e-IND) status for treatment of mpox but also is not widely available in the United States.¹⁷ Intravenous vaccinia immune globulin is under consideration for high-risk individuals, but little is known regarding its efficacy against mpox.^5,16,17

Two smallpox vaccines—JYNNEOS (Bavarian Nordic) and ACAM2000 (Emergent Bio Solutions)—are available for both preexposure and postexposure prophylaxis against mpox virus.¹⁹ At this time, only JYNNEOS is FDA approved for the prevention of mpox; ACAM2000 can be used against mpox under the FDA’s EA-IND protocol, which involves additional requirements, including informed consent from the patient.²⁰ ACAM2000 is a live, replication-competent vaccine that carries a warning of increased risk for side effects in patients with cardiac disease, pregnancy, immunocompromise, and a history or presence of eczema and other skin conditions.^3,21,22 JYNNEOS is a live but replication-deficient virus and therefore does not carry these warnings.^3,21,22

Final Thoughts

Mpox is no longer an obscure illness occurring in limited geographic areas. Dermatologists must remain highly vigilant when evaluating any patient for new-onset vesicular or pustular eruptions to combat this ongoing public health threat. This issue of Cutis^® also features a thorough mpox update on the clinical presentation, vaccine guidance, and management.²³

The 2022 mpox (monkeypox) virus outbreak represents the latest example of how infectious diseases with previously limited reach can spread in a globalized society. More than 86,000 cases have been reported worldwide, with more than 30,000 cases in the United States as of March 15, 2023.¹ Herein, we summarize the key features of mpox infection for the dermatologist.

Mpox Transmission

The mpox virus is a double-stranded DNA virus of the Orthopoxvirus genus and Poxviridae family.^2,3 There are 2 types of the mpox virus: clade I (formerly the Congo Basin clade) and clade II (formerly the West African clade). Clade I causes more severe disease (10% mortality rate), while clade II is associated with lower mortality (1%–3%) and has been split into subclades of IIa (exhibits zoonotic transmission) and IIb (exhibits human-to-human spread).^3,4 The current outbreak is caused by clade IIb, and patients typically have no travel history to classic endemic regions.^5,6

In endemic countries, mpox transmission is zoonotic from small forest animals. In nonendemic countries, sporadic cases rarely have been reported, including a cluster in the United States in 2003 related to pet prairie dogs. In stark contrast, human-to-human transmission is occurring in the current epidemic mainly via intimate skin-to-skin contact and possibly via sexual fluids, meeting the criteria for a sexually transmitted infection. However, nonsexual transmission does still occur, though it is less common.⁷ Many of the reported cases so far are in young to middle-aged men who have sex with men (MSM).^2,8 However, it is crucial to understand that mpox is not exclusive to the MSM population; the virus has been transmitted to heterosexual males, females, children, and even household pets of infected individuals.^2,9,10 Labeling mpox as exclusive to the MSM community is both inaccurate and inappropriately stigmatizing.

Cutaneous Presentation and Diagnosis of Mpox

Mpox has an incubation time of approximately 9 days (range, 7–21 days), after which affected persons develop macular lesions that evolve over 2 to 4 weeks into papules, vesicles, and deep-seated pustules before crusting over and resolving with possible residual scarring.^{2,3,5,9,11,12} Palmoplantar involvement is a key feature.¹¹ Although in some cases there will be multiple lesions with centrifugal progression, the lesions also may be few in number, with some patients presenting with a single lesion in the anogenital region or on the face, hand, or foot (Figure).^6,9 Systemic symptoms such as prodromal fever, lymphadenopathy, and headache are common but not universal.^9,13 Potential complications include penile edema, proctitis, bacterial superinfection, tonsillitis, conjunctivitis, encephalitis, and pneumonia.^5,9,13

Images used with permission from Roneet Lev, MD (San Diego, California), and VisualDx.

A high index of suspicion is needed to diagnose mpox infection. The differential diagnosis includes smallpox; varicella-zoster virus (primary or reactivation); secondary syphilis; measles; herpes simplex virus; molluscum contagiosum; hand, foot, and mouth disease; and disseminated gonococcal infection.^2,3 For lesions confined to the genital area, sexually transmitted infections (eg, chancroid, lymphogranuloma venereum) as well as non–sexually related acute genital ulcers (Lipschütz ulcers) should be considered.²

Certain clinical features may help in distinguishing mpox from other diseases. Mpox exhibits synchronous progression and centrifugal distribution when multiple lesions are present; in contrast, the lesions of primary varicella (chickenpox) appear in multiple different stages, and those of localized herpes zoster (shingles) exhibit a dermatomal distribution. When these features are present, mpox causes a greater degree of lymphadenopathy and systemic symptoms than primary varicella.³Clinical diagnosis of mpox is more than 90% sensitive but only 9% to 26% specific.³ To confirm the diagnosis, a viral swab vigorously obtained from active skin lesions should be sent in viral transport media for mpox DNA-specific polymerase chain reaction testing, which is available from major laboratories.^2,3 Other supportive tests include serum studies for anti–mpox virus immunoglobulins and immunohistochemical staining for viral antigens on skin biopsy specimens.² When evaluating suspected and confirmed mpox cases, dermatologists should wear a gown, gloves, a fitted N95 mask, and eye protection to prevent infection.⁵

Treating Mpox

Symptomatic mpox infection can last for up to 2 to 5 weeks.³ The patient is no longer infectious once the lesions have crusted over.^3,11 The majority of cases require supportive care only.^2,3,5,14 However, mpox remains a potentially fatal disease, with 38 deaths to date in the current outbreak.¹ High-risk populations include children younger than 8 years, pregnant women, and individuals who are immunocompromised.¹⁵ Tecovirimat, an antiviral medication approved by the US Food and Drug Administration (FDA) for smallpox, is available via the expanded access Investigational New Drug (EA-IND) protocol to treat severe mpox cases but is not widely available in the United States.^6,16-18 Brincidofovir, a prodrug of the antiviral cidofovir, possesses single-patient emergency use Investigational New Drug (e-IND) status for treatment of mpox but also is not widely available in the United States.¹⁷ Intravenous vaccinia immune globulin is under consideration for high-risk individuals, but little is known regarding its efficacy against mpox.^5,16,17

Two smallpox vaccines—JYNNEOS (Bavarian Nordic) and ACAM2000 (Emergent Bio Solutions)—are available for both preexposure and postexposure prophylaxis against mpox virus.¹⁹ At this time, only JYNNEOS is FDA approved for the prevention of mpox; ACAM2000 can be used against mpox under the FDA’s EA-IND protocol, which involves additional requirements, including informed consent from the patient.²⁰ ACAM2000 is a live, replication-competent vaccine that carries a warning of increased risk for side effects in patients with cardiac disease, pregnancy, immunocompromise, and a history or presence of eczema and other skin conditions.^3,21,22 JYNNEOS is a live but replication-deficient virus and therefore does not carry these warnings.^3,21,22

Final Thoughts

Mpox is no longer an obscure illness occurring in limited geographic areas. Dermatologists must remain highly vigilant when evaluating any patient for new-onset vesicular or pustular eruptions to combat this ongoing public health threat. This issue of Cutis^® also features a thorough mpox update on the clinical presentation, vaccine guidance, and management.²³

The lip is commonly affected by skin cancer because of increased sun exposure and actinic damage, with basal cell carcinoma typically occurring on the upper lip and squamous cell carcinoma (SCC) on the lower lip. The risk for metastatic spread of SCC on the lip is higher than cutaneous SCC on other facial locations but lower than SCC of the oral mucosa.^1,2 If the tumor is operable and the patient has no contraindications to surgery, Mohs micrographic surgery is the preferred treatment, as it allows for maximal healthy tissue preservation and has the lowest recurrence rates.^1-3 Once the tumor is removed and margins are confirmed to be negative, one must consider the options for defect closure, including healing by secondary intention, primary/direct closure, full-thickness skin grafts, local flaps, or free flaps.⁴ Secondary intention may lead to wound contracture and suboptimal functional and cosmetic outcomes. Primary wedge closure can be utilized for optimal functional and cosmetic outcomes when the defect involves less than one-third of the horizontal width of the vermilion. For larger defects, the surgeon must consider a flap or graft. Skin grafts are less favorable than local flaps because they may have different skin color, texture, and hair-bearing properties than the recipient area.^3,5 In addition, grafts require a separate donor site, which means more pain, recovery time, and risk for complications for the patient.³ Free flaps similarly utilize tissue and blood supply from a donor site to repair major tissue loss. Radial forearm free flaps commonly are used for large lip defects but are more extensive, risky, and costly compared to local flaps for smaller defects under local anesthesia or nerve blocks.^6,7 With these considerations, a local lip flap often is the most ideal repair method.

When performing a local lip flap, it is important to consider the functional and aesthetic aspects of the lips. The lower face is more susceptible to distortion and wound contraction after defect repair because it lacks a substantial supportive fibrous network. The dynamics of opposing lip elevator and depressor muscles make the lips a visual focal point and a crucial structure for facial expression, mastication, oral continence, speech phonation, and mouth opening and closing.^2,4,8,9 Aesthetics and symmetry of the lips also are a large part of facial recognition and self-image.⁹

Lip defects are classified as partial thickness involving skin and muscle or full thickness involving skin, muscle, and mucosa. Partial-thickness wounds less than one-third the width of the horizontal lip can be repaired with a primary wedge resection or left to heal by secondary intention if the defect only involves the superficial vermilion.² For defects larger than one-third the width of the horizontal lip, local flaps are favored to allow for closely matched skin and lip mucosa to fill in the defect.⁹ Full-thickness defects are further classified based on defect width compared to total lip width (ie, less than one-third, between one-third and two-thirds, and greater than two-thirds) as well as location (ie, medial, lateral, upper lip, lower lip).^2,10

There are several local lip flap reconstruction options available, and choosing one is based on defect size and location. We provide a succinct review of the indications, risks, and benefits of commonly utilized flaps (Table), as well as artist renderings of all of the flaps (Figure).

Courtesy of Brinda Chellappan, MD (Galveston, Texas).

Vermilion Flaps

Vermilion flaps are used to close partial-thickness defects of the vermilion border, an area that poses unique obstacles of repair with blending distant tissues to match the surroundings.⁸ Goldstein¹¹ developed an adjacent ipsilateral vermilion flap utilizing an arterialized myocutaneous flap for reconstruction of vermilion defects.Later, this technique was modified by Sawada et al¹² into a bilateral adjacent advancement flap for closure of central vermilion defects and may be preferred for defects 2 cm in size or larger. Bilateral flaps are smaller and therefore more viable than unilateral or larger flaps, allowing for a more aesthetic alignment of the vermilion border and preservation of muscle activity because muscle fibers are not cut. This technique also allows for more efficient stretching or medial advancement of the tissue while generating less tension on the distal flap portions. Burow triangles can be utilized if necessary for improved aesthetic outcome.¹

Mucosal Advancement and Split Myomucosal Advancement Flap

The mucosal advancement technique can be considered for tumors that do not involve the adjacent cutaneous skin or the orbicularis oris muscle; thus, the reconstruction involves only the superficial vermilion area.^7,13 Mucosal incisions are made at the gingivobuccal sulcus, and the mucosal flap is elevated off the orbicularis oris muscle and advanced into the defect.¹⁰ A plane of dissection is maintained while preserving the labial artery. Undermining effectively advances wet mucosa into the dry mucosal lip to create a neovermilion. However, the reconstructed lip often appears thinner and will possibly be a different shade compared to the adjacent native lip. These discrepancies become more evident with deeper defects.⁷

There is a risk for cosmetic distortion and scar contraction with advancing the entire mucosa. Eirís et al¹³ described a solution—a bilateral mucosal rotation flap in which the primary incision is made along the entire vermilion border and tissue is undermined to allow advancement of the mucosa. Because the wound closure tension lays across the entire lip, there is less risk for scar contraction, even if the flap movement is unequal on either side of the defect.¹³

Although mucosal advancement flaps are a classic choice for reconstruction following a vermilion defect, other techniques, such as primary closure, should be considered in elderly patients and patients taking anticoagulants because of the risks for flap necrosis, swelling, bruising, hematoma, and dysesthesia, as well as a decrease in the anterior-posterior dimension of the lip. These risks can be attributed to trauma of surrounding tissue and stress secondary to longer overall operating times.¹⁴

Split myomucosal advancement flaps are used in similar scenarios as myomucosal advancement flaps but for larger red lip defects that are less than 50% the length of the upper or lower lip. Split myomucosal advancement flaps utilize an axial flap based on the labial artery, which provides robust vascular supply to the reconstructed area. This vascularity, along with lateral motor innervation of the orbicularis oris, allows for split myomucosal advancement flaps to restore the resected volume, preserve lip function, and minimize postoperative microstomia.⁷

V-Y Advancement Flaps

V-Y advancement flaps are based on a subcutaneous tissue pedicle and are optimal for partial- and full-thickness defects larger than 1 cm on the lateral upper lips, whereas bilateral V-Y advancement flaps are recommended for central lip defects.^15-17 Advantages of V-Y advancement flaps are preserved facial symmetry and maintenance of the oral sphincter and facial nerve function. The undermining portions allow for advancement of a skin flap of similar thickness and contour into the upper or lower lip.¹⁵ Disadvantages include facial asymmetry with larger defects involving the melolabial fold as well as paresthesia after closure. However, in one study, no paresthesia was reported more than 12 months postprocedure.⁴ The biggest disadvantage of the V-Y advancement flap is the kite-shaped scar and possible trapdoor deformity.^5,15 When working medially, the addition of the pincer modification helps avoid blunting of the philtrum and recreates a Cupid’s bow by curling the lateral flap edges medially to resemble a teardrop shape.¹⁷ V-Y advancement flaps for defects of skin and adipose tissue less than 5 mm in size have the highest need for revision surgery; thus, defects of this small size should be repaired primarily.⁴

When using a V-Y advancement flap to correct large defects, there are 3 common complications that may arise: fullness medial to the commissure, a depressed vermilion lip, and a standing cutaneous deformity along the trailing edge of the flap where the Y is formed upon closure of the donor site. To decrease the fullness, a skin excision from the inferior border of the flap along the vermiliocutaneous border can be made to debulk the area. A vermilion advancement can be used to optimize the vermiliocutaneous junction. Potential standing cutaneous deformity is addressed by excising a small ellipse of skin oriented along the axis of the relaxed skin tension lines.¹⁵

Abbé-Estlander Flap

The Abbé-Estlander flap (also known as a transoral cross-lip flap) is a full-thickness myocutaneous interpolation flap with blood supply from the labial artery. It is used for lower lip tumors that have deep invasion into muscle and are 30% to 60% of the horizontal lip.^8,9 Abbé transposition flaps are used for defects medial to the oral commissure and are best suited for philtrum reconstruction, whereas Estlander flaps are for defects that involve the oral commissure.^9,18 Interpolation flaps usually are performed in 2 stages, but some dermatologic surgeons have reported success with single-stage procedures.¹ The second-stage division usually is performed 2 to 3 weeks after flap insetting to allow time for neovascularization, which is crucial for pedicle survival.^8,9,19

Advantages of this type of flap are the preservation of orbicularis oris strength and a functional and aesthetic result with minimal change in appearance for defects sized from one-third to two-thirds the width of the lip.²⁰ This aesthetic effect is particularly notable when the donor flap is taken from the mediolateral upper lip, allowing the scarred area to blend into the nasolabial fold.⁸ Disadvantages of this flap are a risk for microstomia, lip vermilion misalignment, and lip adhesion.²¹ It is important that patients are educated on the need for multiple surgeries when using this type of flap, as patients favor single-step procedures.¹ The Abbé flap requires 2 surgeries, whereas the Estlander flap requires only 1. However, patients commonly require commissuroplasty with the Estlander flap alone.²¹

Gillies Fan Flap, Karapandzic Flap, Bernard-Webster Flap, and Bernard-Burrow-Webster Flap

The Gillies fan flap, Karapandzic flap, Bernard-Webster (BW) flap, and modified Bernard-Burrow-Webster flap are the likely choices for repair of lip defects that encompass more than two-thirds of the lip.^9,10,22 The Karapandzic and BW flaps are the 2 most frequently used for reconstruction of larger lower lip defects and only require 1 surgery.

Upper lip full-thickness defects that are too big for an Abbé-Estlander flap are closed with the Gillies fan flap.¹⁸ These defects involve 70% to 80% of the horizontal lip.⁹ The Gillies fan flap design redistributes the remaining lip to provide similar tissue quality and texture to fill the large defects.^9,23 Compared to Karapandzic and Bernard flaps, Gillies fan incision closures are hidden well in the nasolabial folds, and the degree of microstomy is decreased because of the rotation of the flaps. However, rotation of medial cheek flaps can distort the orbicular muscular fibers and the anatomy of the commissure, which may require repair with commissurotomy. Drawbacks include a risk for denervation that can result in temporary oral sphincter incompetence.²³ The bilateral Gillies fan flap carries a risk for microstomy as well as misalignment of the lip vermilion and round commissures.²¹

The Karapandzic flap is similar to the Gillies fan flap but only involves the skin and mucosa.⁹ This flap can be used for lateral or medial upper lip defects greater than one-third the width of the entire lip. This single-procedure flap allows for labial continuity, preserved sensation, and motor function; however, microstomia and misalignment of the oral commissure are common.^1,18,21 In a retrospective study by Nicholas et al,⁴ the only flap reported to have a poor functional outcome was the Karapandzic flap, with 3 patients reporting altered sensation and 1 patient reporting persistent stiffness while smiling.

The BW flap can be applied for extensive full-thickness defects greater than one-third the lower lip and for defects with limited residual lip. This flap also can be used in cases where only skin is excised, as the flap does not depend on reminiscent lip tissue for reconstruction of the new lower lip. Sensory function is maintained given adequate visualization and preservation of the local vascular, nervous, and muscular systems. Disadvantages of the BW flap include an incision notch in the region of the lower lip; blunting of the alveolobuccal sulcus; and functional deficits, such as lip incontinence to liquids during the postoperative period.²¹

The Bernard-Burrow-Webster flap is used for large lower lip defects and preserves the oral commissures by advancing adjacent cheek tissue and remaining lip tissue medially.¹⁰ It allows for larger site mobilization, but it is possible to see some resulting oral incontinence.^1,10 The Burow wedge flap is a variant of the advancement flap, with the Burow triangle located lateral to the oral commissure. Caution must be taken to avoid intraoperative bleeding from the labial and angular arteries. In addition, there also may be downward displacement of the vermilion border.⁵

How to Choose a Flap

The orbicularis oris is a circular muscle that surrounds both the upper and lower lips. It is pulled into an oval, allowing for sphincter function by radially oriented muscles, all of which are innervated by the facial nerve. Other key anatomical structures of the lips include the tubercle (vermilion prominence), Cupid’s bow and philtrum, nasolabial folds, white roll, hair-bearing area, and vermilion border. The lips are divided into cutaneous, mucosal, and vermilion parts, with the vermilion area divided into dry/external and wet/internal areas. Sensation to the upper lip is provided by the maxillary division of the trigeminal nerve via the infraorbital nerve. The lower lip is innervated by the mandibular division of the trigeminal nerve via the inferior alveolar nerve. The labial artery, a branch of the facial artery, is responsible for blood supply to the lips.^3,9 Because of the complex anatomy of the lips, careful reconstruction is crucial for functional and aesthetic preservation.

There are a variety of lip defect repairs, but all local flaps aim to preserve aesthetics and function. The Table summarizes the key risks and benefits of each flap. Local flap techniques can be used in combination for more complex defects.³ For example, Nadiminti et al¹⁹ described the combination of the Abbé flap and V-Y advancement flap to restore function and create a new symmetric nasolabial fold. Dermatologic surgeons will determine the most suitable technique based on tumor location, tumor stage or depth of invasion (partial or full thickness), and preservation of function and aesthetics.¹

Other factors to consider when choosing a local flap are the patient’s age, tissue laxity, dentition/need for dentures, and any prior treatments.⁷ Scar revision surgery may be needed after reconstruction, especially with longer vertical scars in areas without other rhytides. In addition, paresthesia is common after Mohs micrographic surgery of the face; however, new neural networks are created postoperatively, and most paresthesia resolves within 1 year of the repair.⁴ Dermabrasion and Z-plasty also may be considered, as they have been shown to be successful in improving final outcomes.⁹ Overall, local flaps have risks for infection, flap necrosis, and bleeding, though the incidence is low in reconstructions of the face.

Final Thoughts

There are several mechanisms to repair upper and lower lip defects resulting from surgical removal of cutaneous cancers. This review of specific flaps used in lip reconstruction provides a comprehensive overview of indications, advantages, and disadvantages of available lip flaps.

The lip is commonly affected by skin cancer because of increased sun exposure and actinic damage, with basal cell carcinoma typically occurring on the upper lip and squamous cell carcinoma (SCC) on the lower lip. The risk for metastatic spread of SCC on the lip is higher than cutaneous SCC on other facial locations but lower than SCC of the oral mucosa.^1,2 If the tumor is operable and the patient has no contraindications to surgery, Mohs micrographic surgery is the preferred treatment, as it allows for maximal healthy tissue preservation and has the lowest recurrence rates.^1-3 Once the tumor is removed and margins are confirmed to be negative, one must consider the options for defect closure, including healing by secondary intention, primary/direct closure, full-thickness skin grafts, local flaps, or free flaps.⁴ Secondary intention may lead to wound contracture and suboptimal functional and cosmetic outcomes. Primary wedge closure can be utilized for optimal functional and cosmetic outcomes when the defect involves less than one-third of the horizontal width of the vermilion. For larger defects, the surgeon must consider a flap or graft. Skin grafts are less favorable than local flaps because they may have different skin color, texture, and hair-bearing properties than the recipient area.^3,5 In addition, grafts require a separate donor site, which means more pain, recovery time, and risk for complications for the patient.³ Free flaps similarly utilize tissue and blood supply from a donor site to repair major tissue loss. Radial forearm free flaps commonly are used for large lip defects but are more extensive, risky, and costly compared to local flaps for smaller defects under local anesthesia or nerve blocks.^6,7 With these considerations, a local lip flap often is the most ideal repair method.

When performing a local lip flap, it is important to consider the functional and aesthetic aspects of the lips. The lower face is more susceptible to distortion and wound contraction after defect repair because it lacks a substantial supportive fibrous network. The dynamics of opposing lip elevator and depressor muscles make the lips a visual focal point and a crucial structure for facial expression, mastication, oral continence, speech phonation, and mouth opening and closing.^2,4,8,9 Aesthetics and symmetry of the lips also are a large part of facial recognition and self-image.⁹

Lip defects are classified as partial thickness involving skin and muscle or full thickness involving skin, muscle, and mucosa. Partial-thickness wounds less than one-third the width of the horizontal lip can be repaired with a primary wedge resection or left to heal by secondary intention if the defect only involves the superficial vermilion.² For defects larger than one-third the width of the horizontal lip, local flaps are favored to allow for closely matched skin and lip mucosa to fill in the defect.⁹ Full-thickness defects are further classified based on defect width compared to total lip width (ie, less than one-third, between one-third and two-thirds, and greater than two-thirds) as well as location (ie, medial, lateral, upper lip, lower lip).^2,10

There are several local lip flap reconstruction options available, and choosing one is based on defect size and location. We provide a succinct review of the indications, risks, and benefits of commonly utilized flaps (Table), as well as artist renderings of all of the flaps (Figure).

Courtesy of Brinda Chellappan, MD (Galveston, Texas).

Vermilion Flaps

Vermilion flaps are used to close partial-thickness defects of the vermilion border, an area that poses unique obstacles of repair with blending distant tissues to match the surroundings.⁸ Goldstein¹¹ developed an adjacent ipsilateral vermilion flap utilizing an arterialized myocutaneous flap for reconstruction of vermilion defects.Later, this technique was modified by Sawada et al¹² into a bilateral adjacent advancement flap for closure of central vermilion defects and may be preferred for defects 2 cm in size or larger. Bilateral flaps are smaller and therefore more viable than unilateral or larger flaps, allowing for a more aesthetic alignment of the vermilion border and preservation of muscle activity because muscle fibers are not cut. This technique also allows for more efficient stretching or medial advancement of the tissue while generating less tension on the distal flap portions. Burow triangles can be utilized if necessary for improved aesthetic outcome.¹

Mucosal Advancement and Split Myomucosal Advancement Flap

The mucosal advancement technique can be considered for tumors that do not involve the adjacent cutaneous skin or the orbicularis oris muscle; thus, the reconstruction involves only the superficial vermilion area.^7,13 Mucosal incisions are made at the gingivobuccal sulcus, and the mucosal flap is elevated off the orbicularis oris muscle and advanced into the defect.¹⁰ A plane of dissection is maintained while preserving the labial artery. Undermining effectively advances wet mucosa into the dry mucosal lip to create a neovermilion. However, the reconstructed lip often appears thinner and will possibly be a different shade compared to the adjacent native lip. These discrepancies become more evident with deeper defects.⁷

There is a risk for cosmetic distortion and scar contraction with advancing the entire mucosa. Eirís et al¹³ described a solution—a bilateral mucosal rotation flap in which the primary incision is made along the entire vermilion border and tissue is undermined to allow advancement of the mucosa. Because the wound closure tension lays across the entire lip, there is less risk for scar contraction, even if the flap movement is unequal on either side of the defect.¹³

Although mucosal advancement flaps are a classic choice for reconstruction following a vermilion defect, other techniques, such as primary closure, should be considered in elderly patients and patients taking anticoagulants because of the risks for flap necrosis, swelling, bruising, hematoma, and dysesthesia, as well as a decrease in the anterior-posterior dimension of the lip. These risks can be attributed to trauma of surrounding tissue and stress secondary to longer overall operating times.¹⁴

Split myomucosal advancement flaps are used in similar scenarios as myomucosal advancement flaps but for larger red lip defects that are less than 50% the length of the upper or lower lip. Split myomucosal advancement flaps utilize an axial flap based on the labial artery, which provides robust vascular supply to the reconstructed area. This vascularity, along with lateral motor innervation of the orbicularis oris, allows for split myomucosal advancement flaps to restore the resected volume, preserve lip function, and minimize postoperative microstomia.⁷

V-Y Advancement Flaps

V-Y advancement flaps are based on a subcutaneous tissue pedicle and are optimal for partial- and full-thickness defects larger than 1 cm on the lateral upper lips, whereas bilateral V-Y advancement flaps are recommended for central lip defects.^15-17 Advantages of V-Y advancement flaps are preserved facial symmetry and maintenance of the oral sphincter and facial nerve function. The undermining portions allow for advancement of a skin flap of similar thickness and contour into the upper or lower lip.¹⁵ Disadvantages include facial asymmetry with larger defects involving the melolabial fold as well as paresthesia after closure. However, in one study, no paresthesia was reported more than 12 months postprocedure.⁴ The biggest disadvantage of the V-Y advancement flap is the kite-shaped scar and possible trapdoor deformity.^5,15 When working medially, the addition of the pincer modification helps avoid blunting of the philtrum and recreates a Cupid’s bow by curling the lateral flap edges medially to resemble a teardrop shape.¹⁷ V-Y advancement flaps for defects of skin and adipose tissue less than 5 mm in size have the highest need for revision surgery; thus, defects of this small size should be repaired primarily.⁴

When using a V-Y advancement flap to correct large defects, there are 3 common complications that may arise: fullness medial to the commissure, a depressed vermilion lip, and a standing cutaneous deformity along the trailing edge of the flap where the Y is formed upon closure of the donor site. To decrease the fullness, a skin excision from the inferior border of the flap along the vermiliocutaneous border can be made to debulk the area. A vermilion advancement can be used to optimize the vermiliocutaneous junction. Potential standing cutaneous deformity is addressed by excising a small ellipse of skin oriented along the axis of the relaxed skin tension lines.¹⁵

Abbé-Estlander Flap

The Abbé-Estlander flap (also known as a transoral cross-lip flap) is a full-thickness myocutaneous interpolation flap with blood supply from the labial artery. It is used for lower lip tumors that have deep invasion into muscle and are 30% to 60% of the horizontal lip.^8,9 Abbé transposition flaps are used for defects medial to the oral commissure and are best suited for philtrum reconstruction, whereas Estlander flaps are for defects that involve the oral commissure.^9,18 Interpolation flaps usually are performed in 2 stages, but some dermatologic surgeons have reported success with single-stage procedures.¹ The second-stage division usually is performed 2 to 3 weeks after flap insetting to allow time for neovascularization, which is crucial for pedicle survival.^8,9,19

Advantages of this type of flap are the preservation of orbicularis oris strength and a functional and aesthetic result with minimal change in appearance for defects sized from one-third to two-thirds the width of the lip.²⁰ This aesthetic effect is particularly notable when the donor flap is taken from the mediolateral upper lip, allowing the scarred area to blend into the nasolabial fold.⁸ Disadvantages of this flap are a risk for microstomia, lip vermilion misalignment, and lip adhesion.²¹ It is important that patients are educated on the need for multiple surgeries when using this type of flap, as patients favor single-step procedures.¹ The Abbé flap requires 2 surgeries, whereas the Estlander flap requires only 1. However, patients commonly require commissuroplasty with the Estlander flap alone.²¹

Gillies Fan Flap, Karapandzic Flap, Bernard-Webster Flap, and Bernard-Burrow-Webster Flap

The Gillies fan flap, Karapandzic flap, Bernard-Webster (BW) flap, and modified Bernard-Burrow-Webster flap are the likely choices for repair of lip defects that encompass more than two-thirds of the lip.^9,10,22 The Karapandzic and BW flaps are the 2 most frequently used for reconstruction of larger lower lip defects and only require 1 surgery.

Upper lip full-thickness defects that are too big for an Abbé-Estlander flap are closed with the Gillies fan flap.¹⁸ These defects involve 70% to 80% of the horizontal lip.⁹ The Gillies fan flap design redistributes the remaining lip to provide similar tissue quality and texture to fill the large defects.^9,23 Compared to Karapandzic and Bernard flaps, Gillies fan incision closures are hidden well in the nasolabial folds, and the degree of microstomy is decreased because of the rotation of the flaps. However, rotation of medial cheek flaps can distort the orbicular muscular fibers and the anatomy of the commissure, which may require repair with commissurotomy. Drawbacks include a risk for denervation that can result in temporary oral sphincter incompetence.²³ The bilateral Gillies fan flap carries a risk for microstomy as well as misalignment of the lip vermilion and round commissures.²¹

The Karapandzic flap is similar to the Gillies fan flap but only involves the skin and mucosa.⁹ This flap can be used for lateral or medial upper lip defects greater than one-third the width of the entire lip. This single-procedure flap allows for labial continuity, preserved sensation, and motor function; however, microstomia and misalignment of the oral commissure are common.^1,18,21 In a retrospective study by Nicholas et al,⁴ the only flap reported to have a poor functional outcome was the Karapandzic flap, with 3 patients reporting altered sensation and 1 patient reporting persistent stiffness while smiling.

The BW flap can be applied for extensive full-thickness defects greater than one-third the lower lip and for defects with limited residual lip. This flap also can be used in cases where only skin is excised, as the flap does not depend on reminiscent lip tissue for reconstruction of the new lower lip. Sensory function is maintained given adequate visualization and preservation of the local vascular, nervous, and muscular systems. Disadvantages of the BW flap include an incision notch in the region of the lower lip; blunting of the alveolobuccal sulcus; and functional deficits, such as lip incontinence to liquids during the postoperative period.²¹

The Bernard-Burrow-Webster flap is used for large lower lip defects and preserves the oral commissures by advancing adjacent cheek tissue and remaining lip tissue medially.¹⁰ It allows for larger site mobilization, but it is possible to see some resulting oral incontinence.^1,10 The Burow wedge flap is a variant of the advancement flap, with the Burow triangle located lateral to the oral commissure. Caution must be taken to avoid intraoperative bleeding from the labial and angular arteries. In addition, there also may be downward displacement of the vermilion border.⁵

How to Choose a Flap

The orbicularis oris is a circular muscle that surrounds both the upper and lower lips. It is pulled into an oval, allowing for sphincter function by radially oriented muscles, all of which are innervated by the facial nerve. Other key anatomical structures of the lips include the tubercle (vermilion prominence), Cupid’s bow and philtrum, nasolabial folds, white roll, hair-bearing area, and vermilion border. The lips are divided into cutaneous, mucosal, and vermilion parts, with the vermilion area divided into dry/external and wet/internal areas. Sensation to the upper lip is provided by the maxillary division of the trigeminal nerve via the infraorbital nerve. The lower lip is innervated by the mandibular division of the trigeminal nerve via the inferior alveolar nerve. The labial artery, a branch of the facial artery, is responsible for blood supply to the lips.^3,9 Because of the complex anatomy of the lips, careful reconstruction is crucial for functional and aesthetic preservation.

There are a variety of lip defect repairs, but all local flaps aim to preserve aesthetics and function. The Table summarizes the key risks and benefits of each flap. Local flap techniques can be used in combination for more complex defects.³ For example, Nadiminti et al¹⁹ described the combination of the Abbé flap and V-Y advancement flap to restore function and create a new symmetric nasolabial fold. Dermatologic surgeons will determine the most suitable technique based on tumor location, tumor stage or depth of invasion (partial or full thickness), and preservation of function and aesthetics.¹

Other factors to consider when choosing a local flap are the patient’s age, tissue laxity, dentition/need for dentures, and any prior treatments.⁷ Scar revision surgery may be needed after reconstruction, especially with longer vertical scars in areas without other rhytides. In addition, paresthesia is common after Mohs micrographic surgery of the face; however, new neural networks are created postoperatively, and most paresthesia resolves within 1 year of the repair.⁴ Dermabrasion and Z-plasty also may be considered, as they have been shown to be successful in improving final outcomes.⁹ Overall, local flaps have risks for infection, flap necrosis, and bleeding, though the incidence is low in reconstructions of the face.

Final Thoughts

There are several mechanisms to repair upper and lower lip defects resulting from surgical removal of cutaneous cancers. This review of specific flaps used in lip reconstruction provides a comprehensive overview of indications, advantages, and disadvantages of available lip flaps.

The lip is commonly affected by skin cancer because of increased sun exposure and actinic damage, with basal cell carcinoma typically occurring on the upper lip and squamous cell carcinoma (SCC) on the lower lip. The risk for metastatic spread of SCC on the lip is higher than cutaneous SCC on other facial locations but lower than SCC of the oral mucosa.^1,2 If the tumor is operable and the patient has no contraindications to surgery, Mohs micrographic surgery is the preferred treatment, as it allows for maximal healthy tissue preservation and has the lowest recurrence rates.^1-3 Once the tumor is removed and margins are confirmed to be negative, one must consider the options for defect closure, including healing by secondary intention, primary/direct closure, full-thickness skin grafts, local flaps, or free flaps.⁴ Secondary intention may lead to wound contracture and suboptimal functional and cosmetic outcomes. Primary wedge closure can be utilized for optimal functional and cosmetic outcomes when the defect involves less than one-third of the horizontal width of the vermilion. For larger defects, the surgeon must consider a flap or graft. Skin grafts are less favorable than local flaps because they may have different skin color, texture, and hair-bearing properties than the recipient area.^3,5 In addition, grafts require a separate donor site, which means more pain, recovery time, and risk for complications for the patient.³ Free flaps similarly utilize tissue and blood supply from a donor site to repair major tissue loss. Radial forearm free flaps commonly are used for large lip defects but are more extensive, risky, and costly compared to local flaps for smaller defects under local anesthesia or nerve blocks.^6,7 With these considerations, a local lip flap often is the most ideal repair method.

When performing a local lip flap, it is important to consider the functional and aesthetic aspects of the lips. The lower face is more susceptible to distortion and wound contraction after defect repair because it lacks a substantial supportive fibrous network. The dynamics of opposing lip elevator and depressor muscles make the lips a visual focal point and a crucial structure for facial expression, mastication, oral continence, speech phonation, and mouth opening and closing.^2,4,8,9 Aesthetics and symmetry of the lips also are a large part of facial recognition and self-image.⁹

Lip defects are classified as partial thickness involving skin and muscle or full thickness involving skin, muscle, and mucosa. Partial-thickness wounds less than one-third the width of the horizontal lip can be repaired with a primary wedge resection or left to heal by secondary intention if the defect only involves the superficial vermilion.² For defects larger than one-third the width of the horizontal lip, local flaps are favored to allow for closely matched skin and lip mucosa to fill in the defect.⁹ Full-thickness defects are further classified based on defect width compared to total lip width (ie, less than one-third, between one-third and two-thirds, and greater than two-thirds) as well as location (ie, medial, lateral, upper lip, lower lip).^2,10

There are several local lip flap reconstruction options available, and choosing one is based on defect size and location. We provide a succinct review of the indications, risks, and benefits of commonly utilized flaps (Table), as well as artist renderings of all of the flaps (Figure).

Courtesy of Brinda Chellappan, MD (Galveston, Texas).

Vermilion Flaps

Vermilion flaps are used to close partial-thickness defects of the vermilion border, an area that poses unique obstacles of repair with blending distant tissues to match the surroundings.⁸ Goldstein¹¹ developed an adjacent ipsilateral vermilion flap utilizing an arterialized myocutaneous flap for reconstruction of vermilion defects.Later, this technique was modified by Sawada et al¹² into a bilateral adjacent advancement flap for closure of central vermilion defects and may be preferred for defects 2 cm in size or larger. Bilateral flaps are smaller and therefore more viable than unilateral or larger flaps, allowing for a more aesthetic alignment of the vermilion border and preservation of muscle activity because muscle fibers are not cut. This technique also allows for more efficient stretching or medial advancement of the tissue while generating less tension on the distal flap portions. Burow triangles can be utilized if necessary for improved aesthetic outcome.¹

Mucosal Advancement and Split Myomucosal Advancement Flap

The mucosal advancement technique can be considered for tumors that do not involve the adjacent cutaneous skin or the orbicularis oris muscle; thus, the reconstruction involves only the superficial vermilion area.^7,13 Mucosal incisions are made at the gingivobuccal sulcus, and the mucosal flap is elevated off the orbicularis oris muscle and advanced into the defect.¹⁰ A plane of dissection is maintained while preserving the labial artery. Undermining effectively advances wet mucosa into the dry mucosal lip to create a neovermilion. However, the reconstructed lip often appears thinner and will possibly be a different shade compared to the adjacent native lip. These discrepancies become more evident with deeper defects.⁷

There is a risk for cosmetic distortion and scar contraction with advancing the entire mucosa. Eirís et al¹³ described a solution—a bilateral mucosal rotation flap in which the primary incision is made along the entire vermilion border and tissue is undermined to allow advancement of the mucosa. Because the wound closure tension lays across the entire lip, there is less risk for scar contraction, even if the flap movement is unequal on either side of the defect.¹³

Although mucosal advancement flaps are a classic choice for reconstruction following a vermilion defect, other techniques, such as primary closure, should be considered in elderly patients and patients taking anticoagulants because of the risks for flap necrosis, swelling, bruising, hematoma, and dysesthesia, as well as a decrease in the anterior-posterior dimension of the lip. These risks can be attributed to trauma of surrounding tissue and stress secondary to longer overall operating times.¹⁴

Split myomucosal advancement flaps are used in similar scenarios as myomucosal advancement flaps but for larger red lip defects that are less than 50% the length of the upper or lower lip. Split myomucosal advancement flaps utilize an axial flap based on the labial artery, which provides robust vascular supply to the reconstructed area. This vascularity, along with lateral motor innervation of the orbicularis oris, allows for split myomucosal advancement flaps to restore the resected volume, preserve lip function, and minimize postoperative microstomia.⁷

V-Y Advancement Flaps

V-Y advancement flaps are based on a subcutaneous tissue pedicle and are optimal for partial- and full-thickness defects larger than 1 cm on the lateral upper lips, whereas bilateral V-Y advancement flaps are recommended for central lip defects.^15-17 Advantages of V-Y advancement flaps are preserved facial symmetry and maintenance of the oral sphincter and facial nerve function. The undermining portions allow for advancement of a skin flap of similar thickness and contour into the upper or lower lip.¹⁵ Disadvantages include facial asymmetry with larger defects involving the melolabial fold as well as paresthesia after closure. However, in one study, no paresthesia was reported more than 12 months postprocedure.⁴ The biggest disadvantage of the V-Y advancement flap is the kite-shaped scar and possible trapdoor deformity.^5,15 When working medially, the addition of the pincer modification helps avoid blunting of the philtrum and recreates a Cupid’s bow by curling the lateral flap edges medially to resemble a teardrop shape.¹⁷ V-Y advancement flaps for defects of skin and adipose tissue less than 5 mm in size have the highest need for revision surgery; thus, defects of this small size should be repaired primarily.⁴

When using a V-Y advancement flap to correct large defects, there are 3 common complications that may arise: fullness medial to the commissure, a depressed vermilion lip, and a standing cutaneous deformity along the trailing edge of the flap where the Y is formed upon closure of the donor site. To decrease the fullness, a skin excision from the inferior border of the flap along the vermiliocutaneous border can be made to debulk the area. A vermilion advancement can be used to optimize the vermiliocutaneous junction. Potential standing cutaneous deformity is addressed by excising a small ellipse of skin oriented along the axis of the relaxed skin tension lines.¹⁵

Abbé-Estlander Flap

The Abbé-Estlander flap (also known as a transoral cross-lip flap) is a full-thickness myocutaneous interpolation flap with blood supply from the labial artery. It is used for lower lip tumors that have deep invasion into muscle and are 30% to 60% of the horizontal lip.^8,9 Abbé transposition flaps are used for defects medial to the oral commissure and are best suited for philtrum reconstruction, whereas Estlander flaps are for defects that involve the oral commissure.^9,18 Interpolation flaps usually are performed in 2 stages, but some dermatologic surgeons have reported success with single-stage procedures.¹ The second-stage division usually is performed 2 to 3 weeks after flap insetting to allow time for neovascularization, which is crucial for pedicle survival.^8,9,19

Advantages of this type of flap are the preservation of orbicularis oris strength and a functional and aesthetic result with minimal change in appearance for defects sized from one-third to two-thirds the width of the lip.²⁰ This aesthetic effect is particularly notable when the donor flap is taken from the mediolateral upper lip, allowing the scarred area to blend into the nasolabial fold.⁸ Disadvantages of this flap are a risk for microstomia, lip vermilion misalignment, and lip adhesion.²¹ It is important that patients are educated on the need for multiple surgeries when using this type of flap, as patients favor single-step procedures.¹ The Abbé flap requires 2 surgeries, whereas the Estlander flap requires only 1. However, patients commonly require commissuroplasty with the Estlander flap alone.²¹

Gillies Fan Flap, Karapandzic Flap, Bernard-Webster Flap, and Bernard-Burrow-Webster Flap

The Gillies fan flap, Karapandzic flap, Bernard-Webster (BW) flap, and modified Bernard-Burrow-Webster flap are the likely choices for repair of lip defects that encompass more than two-thirds of the lip.^9,10,22 The Karapandzic and BW flaps are the 2 most frequently used for reconstruction of larger lower lip defects and only require 1 surgery.

Upper lip full-thickness defects that are too big for an Abbé-Estlander flap are closed with the Gillies fan flap.¹⁸ These defects involve 70% to 80% of the horizontal lip.⁹ The Gillies fan flap design redistributes the remaining lip to provide similar tissue quality and texture to fill the large defects.^9,23 Compared to Karapandzic and Bernard flaps, Gillies fan incision closures are hidden well in the nasolabial folds, and the degree of microstomy is decreased because of the rotation of the flaps. However, rotation of medial cheek flaps can distort the orbicular muscular fibers and the anatomy of the commissure, which may require repair with commissurotomy. Drawbacks include a risk for denervation that can result in temporary oral sphincter incompetence.²³ The bilateral Gillies fan flap carries a risk for microstomy as well as misalignment of the lip vermilion and round commissures.²¹

The Karapandzic flap is similar to the Gillies fan flap but only involves the skin and mucosa.⁹ This flap can be used for lateral or medial upper lip defects greater than one-third the width of the entire lip. This single-procedure flap allows for labial continuity, preserved sensation, and motor function; however, microstomia and misalignment of the oral commissure are common.^1,18,21 In a retrospective study by Nicholas et al,⁴ the only flap reported to have a poor functional outcome was the Karapandzic flap, with 3 patients reporting altered sensation and 1 patient reporting persistent stiffness while smiling.

The BW flap can be applied for extensive full-thickness defects greater than one-third the lower lip and for defects with limited residual lip. This flap also can be used in cases where only skin is excised, as the flap does not depend on reminiscent lip tissue for reconstruction of the new lower lip. Sensory function is maintained given adequate visualization and preservation of the local vascular, nervous, and muscular systems. Disadvantages of the BW flap include an incision notch in the region of the lower lip; blunting of the alveolobuccal sulcus; and functional deficits, such as lip incontinence to liquids during the postoperative period.²¹

The Bernard-Burrow-Webster flap is used for large lower lip defects and preserves the oral commissures by advancing adjacent cheek tissue and remaining lip tissue medially.¹⁰ It allows for larger site mobilization, but it is possible to see some resulting oral incontinence.^1,10 The Burow wedge flap is a variant of the advancement flap, with the Burow triangle located lateral to the oral commissure. Caution must be taken to avoid intraoperative bleeding from the labial and angular arteries. In addition, there also may be downward displacement of the vermilion border.⁵

How to Choose a Flap

The orbicularis oris is a circular muscle that surrounds both the upper and lower lips. It is pulled into an oval, allowing for sphincter function by radially oriented muscles, all of which are innervated by the facial nerve. Other key anatomical structures of the lips include the tubercle (vermilion prominence), Cupid’s bow and philtrum, nasolabial folds, white roll, hair-bearing area, and vermilion border. The lips are divided into cutaneous, mucosal, and vermilion parts, with the vermilion area divided into dry/external and wet/internal areas. Sensation to the upper lip is provided by the maxillary division of the trigeminal nerve via the infraorbital nerve. The lower lip is innervated by the mandibular division of the trigeminal nerve via the inferior alveolar nerve. The labial artery, a branch of the facial artery, is responsible for blood supply to the lips.^3,9 Because of the complex anatomy of the lips, careful reconstruction is crucial for functional and aesthetic preservation.

There are a variety of lip defect repairs, but all local flaps aim to preserve aesthetics and function. The Table summarizes the key risks and benefits of each flap. Local flap techniques can be used in combination for more complex defects.³ For example, Nadiminti et al¹⁹ described the combination of the Abbé flap and V-Y advancement flap to restore function and create a new symmetric nasolabial fold. Dermatologic surgeons will determine the most suitable technique based on tumor location, tumor stage or depth of invasion (partial or full thickness), and preservation of function and aesthetics.¹

Other factors to consider when choosing a local flap are the patient’s age, tissue laxity, dentition/need for dentures, and any prior treatments.⁷ Scar revision surgery may be needed after reconstruction, especially with longer vertical scars in areas without other rhytides. In addition, paresthesia is common after Mohs micrographic surgery of the face; however, new neural networks are created postoperatively, and most paresthesia resolves within 1 year of the repair.⁴ Dermabrasion and Z-plasty also may be considered, as they have been shown to be successful in improving final outcomes.⁹ Overall, local flaps have risks for infection, flap necrosis, and bleeding, though the incidence is low in reconstructions of the face.

Final Thoughts

There are several mechanisms to repair upper and lower lip defects resulting from surgical removal of cutaneous cancers. This review of specific flaps used in lip reconstruction provides a comprehensive overview of indications, advantages, and disadvantages of available lip flaps.

The mpox (monkeypox) virus is a zoonotic orthopox DNA virus that results in a smallpoxlike illness.¹ Vaccination against smallpox protects against other orthopox infections, including mpox; however, unlike smallpox, mpox is notable for a variety of not-yet-confirmed animal reservoirs.² Mpox was first identified in Denmark in 1959 among nonhuman primates imported from Singapore, and the first case of human infection was diagnosed in 1970 in a 9-month-old child in the Democratic Republic of Congo.³ Endemic regions of Africa have had sporadic outbreaks with increasing frequency over time since the cessation of smallpox vaccination in 1980.^2,4 Infections in nonendemic countries have occurred intermittently, including in 2003 in the Midwest United States. This outbreak was traced back to prairie dogs infected by exotic animals imported from the Republic of Ghana.⁵

Two genetic clades of mpox that differ in mortality rates have been identified: clade II (formerly the West African clade) generally is self-limited with an estimated mortality of 1% to 6%, whereas clade I (formerly the Congo Basin clade) is more transmissible, with a mortality of approximately 10%.^2,6,7 Notably, as of May 2, 2022, all polymerase chain reaction–confirmed cases of mpox in nonendemic countries were identified as clade II.⁷ Following the continued international spread of mpox, the Director-General of the World Health Organization (WHO) declared the global outbreak a public health emergency of international concern on July 23, 2022.⁸ As of March 1, 2023, the Centers for Disease Control and Prevention (CDC) reports that there have been more than 86,000 cases of laboratory-confirmed mpox worldwide and 105 deaths, 89 of which occurred in nonendemic regions.⁹

Transmission of Mpox

In endemic countries, cases have been largely reported secondary to zoonotic spillover from contact with an infected animal.⁶ However, in nonendemic countries, mpox often results from human-to-human transmission, primarily via skin-to-skin contact with infected skin, but also may occur indirectly via contaminated fomites such as bedding or clothing, respiratory secretions, or vertical transmission.^6,10 The indirect transmission of mpox via contaminated fomites is controversial, though some studies have shown the virus can survive on surfaces for up to 15 days.¹¹ In the current outbreak, human-to-human transmission has been strongly associated with close contact during sexual activity, particularly among men who have sex with men (MSM), with notable physical concentration of initial lesions in the genital region.¹² Anyone can acquire mpox—infections are not exclusive to MSM populations, and cases have been reported in all demographic groups, including women and children. It is important to avoid stigmatization of MSM to prevent the propagation of homophobia as well as a false sense of complacency in non-MSM populations.¹³

Clinical Presentation of Mpox

The incubation period of mpox has been reported to last up to 21 days and is posited to depend on the mode of transmission, with complex invasive exposures having a shorter duration of approximately 9 days compared to noninvasive exposures, which have a duration of approximately 13 days.¹⁴ In a recent report from the Netherlands, the average incubation time was 8.5 days in 18 men with exposure attributed to sexual encounters with men.¹² Following the incubation period, mpox infection typically presents with nonspecific systemic symptoms such as fever, malaise, sore throat, cough, and headache for approximately 2 days, followed by painful generalized or localized lymphadenopathy 1 to 2 days prior to the onset of skin lesions.^1,15 In a recent report from Portugal of more than 20 confirmed cases of mpox, approximately half of patients denied symptoms or had mild systemic symptoms, suggesting that many patients in the current outbreak do not endorse systemic symptoms.¹⁶

Classic cutaneous lesions are the hallmark feature of mpox.¹⁷ Over a period of 1 to 2 weeks, each lesion progresses through morphologic stages of macule, papule (Figure), vesicle, and pustule, which then crusts over, forming a scab that falls off after another 1 to 2 weeks and can result in dyspigmented or pitted scars.^1,15 Lesions may be deep-seated or umbilicated; previously they were noted to typically start on the face and spread centrifugally, but recent cases have been notable for a predominance of anogenital lesions, often with the anogenital area as the sole or primary area of involvement.¹⁸ Given the high proportion of anogenital lesions in 2022, symptoms such as anogenital pain, tenesmus, and diarrhea are not uncommon.¹⁹ A recent study describing 528 international cases of mpox revealed that 95% of patients presented with a rash; nearly 75% had anogenital lesions; and 41%, 25%, and 10% had involvement of mucosae, the face, and palms/soles, respectively. More than half of patients had fewer than 10 lesions, and 10% presented with a single genital lesion.¹⁹

Given the recent predilection of lesions for the anogenital area, the differential diagnosis of mpox should include other common infections localized to these areas. Unlike herpes simplex and varicella-zoster infections, mpox does not exhibit the classic herpetiform clustering of vesicles, and unlike the painless chancre of syphilis, the lesions of mpox are exquisitely painful. Similar to chancroid, mpox presents with painful genital lesions and lymphadenopathy, and the umbilicated papules of molluscum could easily be confused with mpox lesions. Proctitis caused by many sexually transmitted infections (STIs), including chlamydia and gonorrhea, may be difficult to differentiate from proctitis symptoms of mpox. Co-infection with HIV and other STIs is common among patients developing mpox in 2022, which is not surprising given that the primary mechanism of transmission of mpox at this time is through sexual contact, and cases are more common in patients with multiple recent sexual partners.¹⁹ Considering these shared risk factors and similar presentation of multiple STIs, patients suspected of having an mpox infection should be tested for other STIs, including HIV.

Complications of Mpox

Although mpox generally is characterized by a mild disease course, there is concern for adverse outcomes, particularly in more vulnerable populations, including immunocompromised, pregnant, and pediatric populations. Complications of infection can include sepsis, encephalitis, bronchopneumonia, and ophthalmic complications that can result in loss of vision.^6,17 The most common complications requiring hospitalization in a recent international report of 528 mpox cases were pain management, which was primarily due to severe anogenital pain, followed by soft-tissue superinfection, with other complications including severe pharyngitis limiting oral intake and infection control practices.¹⁹ In addition to severe rectal pain, proctitis and even rectal perforation have been reported.^19,20

Vertical transmission has been described with devastating outcomes in a case series from the Democratic Republic of Congo, where 4 cases of mpox were identified in pregnant women; 3 of these pregnancies resulted in fetal demise.¹⁰ The only fetus to survive was born to a mother with mild infection. In comparison, 2 of 3 mothers with moderate to severe disease experienced spontaneous abortion in the first trimester, and 1 pregnancy ended due to intrauterine demise during the eighteenth week of gestation, likely a complication of mpox. These cases suggest that more severe disease may be linked to worse fetal outcomes.¹⁰ Further epidemiologic studies will be crucial, given the potential implications.

Diagnosis

When considering a diagnosis of mpox, clinicians should inquire about recent travel, living arrangements, sexual history, and recent sick contacts.⁶ A complete skin examination should include the oral and genital areas, given the high prevalence of lesions in these areas. A skin biopsy is not recommended for the diagnosis of mpox, as nonspecific viral changes cannot be differentiated from other viral exanthems, but it often is useful to rule out other differential diagnoses.²¹ Additionally, immunohistochemistry and electron microscopy can be utilized to aid in a histologic diagnosis of mpox.

Polymerase chain reaction detection of orthopox or mpox DNA is the gold standard for diagnosis.⁶ Two swabs should be collected from each lesion by swabbing vigorously using sterile swabs made of a synthetic material such as polyester, nylon, or Dacron and placed into a sterile container or viral transport medium.²² Some laboratories may have different instructions for collection of samples, so clinicians are advised to check for instructions from their local laboratory. Deroofing lesions prior to swabbing is not necessary, and specimens can include lesional material or crust. Collection of specimens from 2 to 3 lesions is recommended, preferably from different body areas or lesions with varying morphologies. Anal or rectal swabs can be considered in patients presenting with anal pain or proctitis with clinical suspicion for mpox based on history.¹⁹

Infection Prevention

Interim guidance from the WHO on November 16, 2022, reiterated the goal of outbreak control primarily via public health measures, which includes targeted use of vaccines for at-risk populations or postexposure prophylactic vaccination within 4 days, but heavily relies on surveillance and containment techniques, such as contact tracing with monitoring of contacts for onset of symptoms and isolation of cases through the complete infectious period.²³ Patients are considered infectious from symptom onset until all cutaneous lesions are re-epithelized and should remain in isolation, including from household contacts and domestic and wildlife animals, for the duration of illness.^24,25 Individuals exposed to humans or animals with confirmed mpox should be monitored for the development of symptoms for 21 days following last known exposure, regardless of vaccination status, and should be instructed to measure their temperature twice daily.²⁶ Pets exposed to mpox should be isolated from other animals and humans for 21 days following last known contact.²⁴ Vaccination strategies for preexposure and postexposure prophylaxis (PEP) are discussed below in further detail. Postinfection, the WHO suggests use of condoms for all oral, vaginal, and anal sexual activity for 12 weeks after recovery.⁷

Patients with suspected or confirmed mpox in a hospital should be in a single private room on special droplet and contact precautions.²⁷ No special air handling or negative pressure isolation is needed unless the patient is undergoing an aerosol-generating procedure (eg, intubation, endoscopy, bronchoscopy). When hospitalized, patients should have a dedicated bathroom, if possible, and at-home patients should be isolated from household members until contagion risk resolves; this includes the use of a separate bathroom, when possible. Health care personnel entering the room of a patient should don appropriate personal protective equipment (PPE), including a disposable gown, gloves, eye protection, and N95 respirator or equivalent. Recommendations include standard practices for cleaning, with wet cleaning methods preferred over dry methods, using a disinfectant that covers emerging viral pathogens, and avoidance of shaking linens to prevent the spread of infectious particles.²⁷ A variety of Environmental Protection Agency–registered wipes with virucidal activity against emerging viruses, including those with active ingredients such as quaternary ammonium, hydrogen peroxide, and hypochlorous acid, should be used for disinfecting surfaces.²⁸

Vaccination

ACAM2000 (Emergent Bio Solutions) and JYNNEOS (Bavarian Nordic)(also known as Imvamune or Imvanex) are available in the United States for the prevention of mpox infection.²⁹ ACAM2000, a second-generation, replication-competent, live smallpox vaccine administered as a single percutaneous injection, is contraindicated in immunocompromised populations, including patients with HIV or on immunosuppressive or biologic therapy, pregnant individuals, people with a history of atopic dermatitis or other exfoliative skin diseases with impaired barrier function, and patients with a history of cardiac disease due to the risk of myocarditis and pericarditis.³⁰

JYNNEOS is a nonreplicating live vaccine approved by the US Food and Drug Administration (FDA) for the prevention of mpox in individuals older than 18 years administered as 2 subcutaneous doses 4 weeks apart. Patients are considered fully vaccinated 2 weeks after the second dose, and JYNNEOS is available to pediatric patients with a single patient expanded access use authorization from the FDA.^29,30 More recently, the FDA issued an emergency use authorization (EUA) for administration of the vaccine to patients younger than 18 years who are at high risk of infection after exposure.³¹ More importantly, the FDA also issued an EUA for the intradermal administration of JYNNEOS at one-fifth of the subcutaneous dose to expand the current vaccine supply. This EUA is based on research by Frey et al,³² which showed that intradermal administration, even at a lower dose, elicited similar immune responses among study participants as the higher dose administered subcutaneously.

JYNNEOS is the preferred vaccine for the prevention of mpox because of its poor ability to replicate in human cells and resultant safety for use in populations that are immunocompromised, pregnant, or have skin barrier defects such as atopic dermatitis, without the risk of myocarditis or pericarditis. However, current supplies are limited. JYNNEOS was specifically studied in patients with atopic dermatitis and has been shown to be safe and effective in patients with a history of atopic dermatitis and active disease with a SCORAD (SCORing Atopic Dermatitis) score of 30 or lower.³³ Of note, JYNNEOS is contraindicated in patients allergic to components of the vaccine, including egg, gentamicin, and ciprofloxacin. Although JYNNEOS is safe to administer to persons with immunocompromising conditions, the CDC reports that such persons might be at increased risk for severe disease if an occupational infection occurs, and in the setting of immunocompromise, such persons may be less likely to mount an effective response to vaccination. Therefore, the risk-benefit ratio should be considered to determine if an immunocompromised person should be vaccinated with JYNNEOS.³⁰

The WHO and the CDC do not recommended mass vaccination of the general public for outbreaks of mpox in nonendemic countries, with immunization reserved for appropriate PEP and pre-exposure prophylaxis in intermediate- to high-risk individuals.^23,26 The CDC recommends PEP vaccination for individuals with a high degree of exposure that includes unprotected contact of the skin or mucous membranes of an individual to the skin, lesions, body fluids, or contaminated fomites from a patient with mpox, as well as being within 6 feet of a patient during an aerosolization procedure without proper PPE. Following an intermediate degree of exposure, which includes being within 6 feet for 3 or more hours wearing at minimum a surgical mask or contact with fomites while wearing incomplete PPE, the CDC recommends monitoring and shared decision-making regarding risks and benefits of PEP vaccination. Monitoring without PEP is indicated for low and uncertain degrees of exposure, including entering a room without full PPE such as eye protection, regardless of the duration of contact.^23,26

Postexposure prophylaxis vaccination should be administered within 4 days of a known high-level exposure to mpox to prevent infection.²⁹ If administered within 4 to 14 days postexposure, vaccination may reduce disease severity but will not prevent infection.³⁴

Pre-exposure prophylaxis is recommended for individuals at high risk for exposure to mpox, including health care workers such as laboratory personnel who handle mpox specimens and health care workers who administer ACAM2000 vaccinations or anticipate providing care for many patients with mpox.³⁴

Management

Most cases of mpox are characterized by mild to moderate disease with a self-limited course. Most commonly, medical management of mpox involves supportive care such as fluid resuscitation, supplemental oxygen, and pain management.⁶ Treatment of superinfected skin lesions may require antibiotics. In the event of ophthalmologic involvement, patients should be referred to an ophthalmologist for further management.

Currently, there are no FDA-approved therapies for mpox; however, tecovirimat, cidofovir, brincidofovir, and vaccinia immune globulin intravenous are available under expanded access Investigational New Drug protocols.^6,35 Human data for cidofovir, brincidofovir, and vaccinia immune globulin intravenous in the treatment of mpox are lacking, while cidofovir and brincidofovir have shown efficacy against orthopoxviruses in in vitro and animal studies, but are available therapeutic options.³⁵

Tecovirimat is an antiviral that is FDA approved for smallpox with efficacy data against mpox in animal studies. It is the first-line treatment for patients with severe disease requiring hospitalization or 1 or more complications, including dehydration or secondary skin infections, as well as for populations at risk for severe disease, which includes immunocompromised patients, pediatric patients younger than 8 years, pregnant or breastfeeding individuals, or patients with a history of atopic dermatitis or active exfoliative skin conditions.³⁶ In this current outbreak, both intravenous and oral tecovirimat are weight based in adult and pediatric patients for 14 days, with the intravenous form dosed every 12 hours by infusion over 6 hours, and the oral doses administered every 8 to 12 hours based on patient weight.³⁷ Tecovirimat generally is well tolerated with mild side effects but is notably contraindicated in patients with severe renal impairment with a creatinine clearance less than 30 mL/min, and renal monitoring is indicated in pediatric patients younger than 2 years and in all patients receiving intravenous treatment.

Conclusion

Given that cutaneous lesions are the most specific presenting sign of mpox infection, dermatologists will play an integral role in identifying future cases and managing future outbreaks. Mpox should be considered in the differential diagnosis for all patients presenting with umbilicated or papulovesicular lesions, particularly in an anogenital distribution. The classic presentation of mpox may be more common among patients who are not considered high risk and have not been exposed via sexual activity. All patients with suspicious lesions should be managed following appropriate infection control precautions and should undergo molecular diagnostic assay of swabbed lesions to confirm the diagnosis. JYNNEOS is the only vaccine that is currently being distributed in the United States and is safe to administer to immunocompromised populations. The risks and benefits of vaccination should be considered on an individual basis between a patient and their provider. Taking into consideration that patients with atopic dermatitis are at risk for severe disease if infected with mpox, vaccination should be strongly encouraged if indicated based on patient risk factors. For atopic dermatitis patients treated with dupilumab, shared decision-making is essential given the FDA label, which recommends avoiding the use of live vaccines.³⁸

The mpox epidemic occurring amidst the ongoing COVID-19 pandemic should serve as a wake-up call to the importance of pandemic preparedness and the global health response strategies in the modern era of globalization. Looking forward, widespread vaccination against mpox may be necessary to control the spread of the disease and to protect vulnerable populations, including pregnant individuals. In the current climate of hesitancy surrounding vaccines and the erosion of trust in public health agencies, it is incumbent upon health care providers to educate patients regarding the role of vaccines and public health measures to control this developing global health crisis.

The mpox (monkeypox) virus is a zoonotic orthopox DNA virus that results in a smallpoxlike illness.¹ Vaccination against smallpox protects against other orthopox infections, including mpox; however, unlike smallpox, mpox is notable for a variety of not-yet-confirmed animal reservoirs.² Mpox was first identified in Denmark in 1959 among nonhuman primates imported from Singapore, and the first case of human infection was diagnosed in 1970 in a 9-month-old child in the Democratic Republic of Congo.³ Endemic regions of Africa have had sporadic outbreaks with increasing frequency over time since the cessation of smallpox vaccination in 1980.^2,4 Infections in nonendemic countries have occurred intermittently, including in 2003 in the Midwest United States. This outbreak was traced back to prairie dogs infected by exotic animals imported from the Republic of Ghana.⁵

Two genetic clades of mpox that differ in mortality rates have been identified: clade II (formerly the West African clade) generally is self-limited with an estimated mortality of 1% to 6%, whereas clade I (formerly the Congo Basin clade) is more transmissible, with a mortality of approximately 10%.^2,6,7 Notably, as of May 2, 2022, all polymerase chain reaction–confirmed cases of mpox in nonendemic countries were identified as clade II.⁷ Following the continued international spread of mpox, the Director-General of the World Health Organization (WHO) declared the global outbreak a public health emergency of international concern on July 23, 2022.⁸ As of March 1, 2023, the Centers for Disease Control and Prevention (CDC) reports that there have been more than 86,000 cases of laboratory-confirmed mpox worldwide and 105 deaths, 89 of which occurred in nonendemic regions.⁹

Transmission of Mpox

In endemic countries, cases have been largely reported secondary to zoonotic spillover from contact with an infected animal.⁶ However, in nonendemic countries, mpox often results from human-to-human transmission, primarily via skin-to-skin contact with infected skin, but also may occur indirectly via contaminated fomites such as bedding or clothing, respiratory secretions, or vertical transmission.^6,10 The indirect transmission of mpox via contaminated fomites is controversial, though some studies have shown the virus can survive on surfaces for up to 15 days.¹¹ In the current outbreak, human-to-human transmission has been strongly associated with close contact during sexual activity, particularly among men who have sex with men (MSM), with notable physical concentration of initial lesions in the genital region.¹² Anyone can acquire mpox—infections are not exclusive to MSM populations, and cases have been reported in all demographic groups, including women and children. It is important to avoid stigmatization of MSM to prevent the propagation of homophobia as well as a false sense of complacency in non-MSM populations.¹³

Clinical Presentation of Mpox

The incubation period of mpox has been reported to last up to 21 days and is posited to depend on the mode of transmission, with complex invasive exposures having a shorter duration of approximately 9 days compared to noninvasive exposures, which have a duration of approximately 13 days.¹⁴ In a recent report from the Netherlands, the average incubation time was 8.5 days in 18 men with exposure attributed to sexual encounters with men.¹² Following the incubation period, mpox infection typically presents with nonspecific systemic symptoms such as fever, malaise, sore throat, cough, and headache for approximately 2 days, followed by painful generalized or localized lymphadenopathy 1 to 2 days prior to the onset of skin lesions.^1,15 In a recent report from Portugal of more than 20 confirmed cases of mpox, approximately half of patients denied symptoms or had mild systemic symptoms, suggesting that many patients in the current outbreak do not endorse systemic symptoms.¹⁶

Classic cutaneous lesions are the hallmark feature of mpox.¹⁷ Over a period of 1 to 2 weeks, each lesion progresses through morphologic stages of macule, papule (Figure), vesicle, and pustule, which then crusts over, forming a scab that falls off after another 1 to 2 weeks and can result in dyspigmented or pitted scars.^1,15 Lesions may be deep-seated or umbilicated; previously they were noted to typically start on the face and spread centrifugally, but recent cases have been notable for a predominance of anogenital lesions, often with the anogenital area as the sole or primary area of involvement.¹⁸ Given the high proportion of anogenital lesions in 2022, symptoms such as anogenital pain, tenesmus, and diarrhea are not uncommon.¹⁹ A recent study describing 528 international cases of mpox revealed that 95% of patients presented with a rash; nearly 75% had anogenital lesions; and 41%, 25%, and 10% had involvement of mucosae, the face, and palms/soles, respectively. More than half of patients had fewer than 10 lesions, and 10% presented with a single genital lesion.¹⁹

Given the recent predilection of lesions for the anogenital area, the differential diagnosis of mpox should include other common infections localized to these areas. Unlike herpes simplex and varicella-zoster infections, mpox does not exhibit the classic herpetiform clustering of vesicles, and unlike the painless chancre of syphilis, the lesions of mpox are exquisitely painful. Similar to chancroid, mpox presents with painful genital lesions and lymphadenopathy, and the umbilicated papules of molluscum could easily be confused with mpox lesions. Proctitis caused by many sexually transmitted infections (STIs), including chlamydia and gonorrhea, may be difficult to differentiate from proctitis symptoms of mpox. Co-infection with HIV and other STIs is common among patients developing mpox in 2022, which is not surprising given that the primary mechanism of transmission of mpox at this time is through sexual contact, and cases are more common in patients with multiple recent sexual partners.¹⁹ Considering these shared risk factors and similar presentation of multiple STIs, patients suspected of having an mpox infection should be tested for other STIs, including HIV.

Complications of Mpox

Although mpox generally is characterized by a mild disease course, there is concern for adverse outcomes, particularly in more vulnerable populations, including immunocompromised, pregnant, and pediatric populations. Complications of infection can include sepsis, encephalitis, bronchopneumonia, and ophthalmic complications that can result in loss of vision.^6,17 The most common complications requiring hospitalization in a recent international report of 528 mpox cases were pain management, which was primarily due to severe anogenital pain, followed by soft-tissue superinfection, with other complications including severe pharyngitis limiting oral intake and infection control practices.¹⁹ In addition to severe rectal pain, proctitis and even rectal perforation have been reported.^19,20

Vertical transmission has been described with devastating outcomes in a case series from the Democratic Republic of Congo, where 4 cases of mpox were identified in pregnant women; 3 of these pregnancies resulted in fetal demise.¹⁰ The only fetus to survive was born to a mother with mild infection. In comparison, 2 of 3 mothers with moderate to severe disease experienced spontaneous abortion in the first trimester, and 1 pregnancy ended due to intrauterine demise during the eighteenth week of gestation, likely a complication of mpox. These cases suggest that more severe disease may be linked to worse fetal outcomes.¹⁰ Further epidemiologic studies will be crucial, given the potential implications.

Diagnosis

When considering a diagnosis of mpox, clinicians should inquire about recent travel, living arrangements, sexual history, and recent sick contacts.⁶ A complete skin examination should include the oral and genital areas, given the high prevalence of lesions in these areas. A skin biopsy is not recommended for the diagnosis of mpox, as nonspecific viral changes cannot be differentiated from other viral exanthems, but it often is useful to rule out other differential diagnoses.²¹ Additionally, immunohistochemistry and electron microscopy can be utilized to aid in a histologic diagnosis of mpox.

Polymerase chain reaction detection of orthopox or mpox DNA is the gold standard for diagnosis.⁶ Two swabs should be collected from each lesion by swabbing vigorously using sterile swabs made of a synthetic material such as polyester, nylon, or Dacron and placed into a sterile container or viral transport medium.²² Some laboratories may have different instructions for collection of samples, so clinicians are advised to check for instructions from their local laboratory. Deroofing lesions prior to swabbing is not necessary, and specimens can include lesional material or crust. Collection of specimens from 2 to 3 lesions is recommended, preferably from different body areas or lesions with varying morphologies. Anal or rectal swabs can be considered in patients presenting with anal pain or proctitis with clinical suspicion for mpox based on history.¹⁹

Infection Prevention

Interim guidance from the WHO on November 16, 2022, reiterated the goal of outbreak control primarily via public health measures, which includes targeted use of vaccines for at-risk populations or postexposure prophylactic vaccination within 4 days, but heavily relies on surveillance and containment techniques, such as contact tracing with monitoring of contacts for onset of symptoms and isolation of cases through the complete infectious period.²³ Patients are considered infectious from symptom onset until all cutaneous lesions are re-epithelized and should remain in isolation, including from household contacts and domestic and wildlife animals, for the duration of illness.^24,25 Individuals exposed to humans or animals with confirmed mpox should be monitored for the development of symptoms for 21 days following last known exposure, regardless of vaccination status, and should be instructed to measure their temperature twice daily.²⁶ Pets exposed to mpox should be isolated from other animals and humans for 21 days following last known contact.²⁴ Vaccination strategies for preexposure and postexposure prophylaxis (PEP) are discussed below in further detail. Postinfection, the WHO suggests use of condoms for all oral, vaginal, and anal sexual activity for 12 weeks after recovery.⁷

Patients with suspected or confirmed mpox in a hospital should be in a single private room on special droplet and contact precautions.²⁷ No special air handling or negative pressure isolation is needed unless the patient is undergoing an aerosol-generating procedure (eg, intubation, endoscopy, bronchoscopy). When hospitalized, patients should have a dedicated bathroom, if possible, and at-home patients should be isolated from household members until contagion risk resolves; this includes the use of a separate bathroom, when possible. Health care personnel entering the room of a patient should don appropriate personal protective equipment (PPE), including a disposable gown, gloves, eye protection, and N95 respirator or equivalent. Recommendations include standard practices for cleaning, with wet cleaning methods preferred over dry methods, using a disinfectant that covers emerging viral pathogens, and avoidance of shaking linens to prevent the spread of infectious particles.²⁷ A variety of Environmental Protection Agency–registered wipes with virucidal activity against emerging viruses, including those with active ingredients such as quaternary ammonium, hydrogen peroxide, and hypochlorous acid, should be used for disinfecting surfaces.²⁸

Vaccination

ACAM2000 (Emergent Bio Solutions) and JYNNEOS (Bavarian Nordic)(also known as Imvamune or Imvanex) are available in the United States for the prevention of mpox infection.²⁹ ACAM2000, a second-generation, replication-competent, live smallpox vaccine administered as a single percutaneous injection, is contraindicated in immunocompromised populations, including patients with HIV or on immunosuppressive or biologic therapy, pregnant individuals, people with a history of atopic dermatitis or other exfoliative skin diseases with impaired barrier function, and patients with a history of cardiac disease due to the risk of myocarditis and pericarditis.³⁰

JYNNEOS is a nonreplicating live vaccine approved by the US Food and Drug Administration (FDA) for the prevention of mpox in individuals older than 18 years administered as 2 subcutaneous doses 4 weeks apart. Patients are considered fully vaccinated 2 weeks after the second dose, and JYNNEOS is available to pediatric patients with a single patient expanded access use authorization from the FDA.^29,30 More recently, the FDA issued an emergency use authorization (EUA) for administration of the vaccine to patients younger than 18 years who are at high risk of infection after exposure.³¹ More importantly, the FDA also issued an EUA for the intradermal administration of JYNNEOS at one-fifth of the subcutaneous dose to expand the current vaccine supply. This EUA is based on research by Frey et al,³² which showed that intradermal administration, even at a lower dose, elicited similar immune responses among study participants as the higher dose administered subcutaneously.

JYNNEOS is the preferred vaccine for the prevention of mpox because of its poor ability to replicate in human cells and resultant safety for use in populations that are immunocompromised, pregnant, or have skin barrier defects such as atopic dermatitis, without the risk of myocarditis or pericarditis. However, current supplies are limited. JYNNEOS was specifically studied in patients with atopic dermatitis and has been shown to be safe and effective in patients with a history of atopic dermatitis and active disease with a SCORAD (SCORing Atopic Dermatitis) score of 30 or lower.³³ Of note, JYNNEOS is contraindicated in patients allergic to components of the vaccine, including egg, gentamicin, and ciprofloxacin. Although JYNNEOS is safe to administer to persons with immunocompromising conditions, the CDC reports that such persons might be at increased risk for severe disease if an occupational infection occurs, and in the setting of immunocompromise, such persons may be less likely to mount an effective response to vaccination. Therefore, the risk-benefit ratio should be considered to determine if an immunocompromised person should be vaccinated with JYNNEOS.³⁰

The WHO and the CDC do not recommended mass vaccination of the general public for outbreaks of mpox in nonendemic countries, with immunization reserved for appropriate PEP and pre-exposure prophylaxis in intermediate- to high-risk individuals.^23,26 The CDC recommends PEP vaccination for individuals with a high degree of exposure that includes unprotected contact of the skin or mucous membranes of an individual to the skin, lesions, body fluids, or contaminated fomites from a patient with mpox, as well as being within 6 feet of a patient during an aerosolization procedure without proper PPE. Following an intermediate degree of exposure, which includes being within 6 feet for 3 or more hours wearing at minimum a surgical mask or contact with fomites while wearing incomplete PPE, the CDC recommends monitoring and shared decision-making regarding risks and benefits of PEP vaccination. Monitoring without PEP is indicated for low and uncertain degrees of exposure, including entering a room without full PPE such as eye protection, regardless of the duration of contact.^23,26

Postexposure prophylaxis vaccination should be administered within 4 days of a known high-level exposure to mpox to prevent infection.²⁹ If administered within 4 to 14 days postexposure, vaccination may reduce disease severity but will not prevent infection.³⁴

Pre-exposure prophylaxis is recommended for individuals at high risk for exposure to mpox, including health care workers such as laboratory personnel who handle mpox specimens and health care workers who administer ACAM2000 vaccinations or anticipate providing care for many patients with mpox.³⁴

Management

Most cases of mpox are characterized by mild to moderate disease with a self-limited course. Most commonly, medical management of mpox involves supportive care such as fluid resuscitation, supplemental oxygen, and pain management.⁶ Treatment of superinfected skin lesions may require antibiotics. In the event of ophthalmologic involvement, patients should be referred to an ophthalmologist for further management.

Currently, there are no FDA-approved therapies for mpox; however, tecovirimat, cidofovir, brincidofovir, and vaccinia immune globulin intravenous are available under expanded access Investigational New Drug protocols.^6,35 Human data for cidofovir, brincidofovir, and vaccinia immune globulin intravenous in the treatment of mpox are lacking, while cidofovir and brincidofovir have shown efficacy against orthopoxviruses in in vitro and animal studies, but are available therapeutic options.³⁵

Tecovirimat is an antiviral that is FDA approved for smallpox with efficacy data against mpox in animal studies. It is the first-line treatment for patients with severe disease requiring hospitalization or 1 or more complications, including dehydration or secondary skin infections, as well as for populations at risk for severe disease, which includes immunocompromised patients, pediatric patients younger than 8 years, pregnant or breastfeeding individuals, or patients with a history of atopic dermatitis or active exfoliative skin conditions.³⁶ In this current outbreak, both intravenous and oral tecovirimat are weight based in adult and pediatric patients for 14 days, with the intravenous form dosed every 12 hours by infusion over 6 hours, and the oral doses administered every 8 to 12 hours based on patient weight.³⁷ Tecovirimat generally is well tolerated with mild side effects but is notably contraindicated in patients with severe renal impairment with a creatinine clearance less than 30 mL/min, and renal monitoring is indicated in pediatric patients younger than 2 years and in all patients receiving intravenous treatment.

Conclusion

Given that cutaneous lesions are the most specific presenting sign of mpox infection, dermatologists will play an integral role in identifying future cases and managing future outbreaks. Mpox should be considered in the differential diagnosis for all patients presenting with umbilicated or papulovesicular lesions, particularly in an anogenital distribution. The classic presentation of mpox may be more common among patients who are not considered high risk and have not been exposed via sexual activity. All patients with suspicious lesions should be managed following appropriate infection control precautions and should undergo molecular diagnostic assay of swabbed lesions to confirm the diagnosis. JYNNEOS is the only vaccine that is currently being distributed in the United States and is safe to administer to immunocompromised populations. The risks and benefits of vaccination should be considered on an individual basis between a patient and their provider. Taking into consideration that patients with atopic dermatitis are at risk for severe disease if infected with mpox, vaccination should be strongly encouraged if indicated based on patient risk factors. For atopic dermatitis patients treated with dupilumab, shared decision-making is essential given the FDA label, which recommends avoiding the use of live vaccines.³⁸

The mpox epidemic occurring amidst the ongoing COVID-19 pandemic should serve as a wake-up call to the importance of pandemic preparedness and the global health response strategies in the modern era of globalization. Looking forward, widespread vaccination against mpox may be necessary to control the spread of the disease and to protect vulnerable populations, including pregnant individuals. In the current climate of hesitancy surrounding vaccines and the erosion of trust in public health agencies, it is incumbent upon health care providers to educate patients regarding the role of vaccines and public health measures to control this developing global health crisis.

The mpox (monkeypox) virus is a zoonotic orthopox DNA virus that results in a smallpoxlike illness.¹ Vaccination against smallpox protects against other orthopox infections, including mpox; however, unlike smallpox, mpox is notable for a variety of not-yet-confirmed animal reservoirs.² Mpox was first identified in Denmark in 1959 among nonhuman primates imported from Singapore, and the first case of human infection was diagnosed in 1970 in a 9-month-old child in the Democratic Republic of Congo.³ Endemic regions of Africa have had sporadic outbreaks with increasing frequency over time since the cessation of smallpox vaccination in 1980.^2,4 Infections in nonendemic countries have occurred intermittently, including in 2003 in the Midwest United States. This outbreak was traced back to prairie dogs infected by exotic animals imported from the Republic of Ghana.⁵

Two genetic clades of mpox that differ in mortality rates have been identified: clade II (formerly the West African clade) generally is self-limited with an estimated mortality of 1% to 6%, whereas clade I (formerly the Congo Basin clade) is more transmissible, with a mortality of approximately 10%.^2,6,7 Notably, as of May 2, 2022, all polymerase chain reaction–confirmed cases of mpox in nonendemic countries were identified as clade II.⁷ Following the continued international spread of mpox, the Director-General of the World Health Organization (WHO) declared the global outbreak a public health emergency of international concern on July 23, 2022.⁸ As of March 1, 2023, the Centers for Disease Control and Prevention (CDC) reports that there have been more than 86,000 cases of laboratory-confirmed mpox worldwide and 105 deaths, 89 of which occurred in nonendemic regions.⁹

Transmission of Mpox

In endemic countries, cases have been largely reported secondary to zoonotic spillover from contact with an infected animal.⁶ However, in nonendemic countries, mpox often results from human-to-human transmission, primarily via skin-to-skin contact with infected skin, but also may occur indirectly via contaminated fomites such as bedding or clothing, respiratory secretions, or vertical transmission.^6,10 The indirect transmission of mpox via contaminated fomites is controversial, though some studies have shown the virus can survive on surfaces for up to 15 days.¹¹ In the current outbreak, human-to-human transmission has been strongly associated with close contact during sexual activity, particularly among men who have sex with men (MSM), with notable physical concentration of initial lesions in the genital region.¹² Anyone can acquire mpox—infections are not exclusive to MSM populations, and cases have been reported in all demographic groups, including women and children. It is important to avoid stigmatization of MSM to prevent the propagation of homophobia as well as a false sense of complacency in non-MSM populations.¹³

Clinical Presentation of Mpox

The incubation period of mpox has been reported to last up to 21 days and is posited to depend on the mode of transmission, with complex invasive exposures having a shorter duration of approximately 9 days compared to noninvasive exposures, which have a duration of approximately 13 days.¹⁴ In a recent report from the Netherlands, the average incubation time was 8.5 days in 18 men with exposure attributed to sexual encounters with men.¹² Following the incubation period, mpox infection typically presents with nonspecific systemic symptoms such as fever, malaise, sore throat, cough, and headache for approximately 2 days, followed by painful generalized or localized lymphadenopathy 1 to 2 days prior to the onset of skin lesions.^1,15 In a recent report from Portugal of more than 20 confirmed cases of mpox, approximately half of patients denied symptoms or had mild systemic symptoms, suggesting that many patients in the current outbreak do not endorse systemic symptoms.¹⁶

Classic cutaneous lesions are the hallmark feature of mpox.¹⁷ Over a period of 1 to 2 weeks, each lesion progresses through morphologic stages of macule, papule (Figure), vesicle, and pustule, which then crusts over, forming a scab that falls off after another 1 to 2 weeks and can result in dyspigmented or pitted scars.^1,15 Lesions may be deep-seated or umbilicated; previously they were noted to typically start on the face and spread centrifugally, but recent cases have been notable for a predominance of anogenital lesions, often with the anogenital area as the sole or primary area of involvement.¹⁸ Given the high proportion of anogenital lesions in 2022, symptoms such as anogenital pain, tenesmus, and diarrhea are not uncommon.¹⁹ A recent study describing 528 international cases of mpox revealed that 95% of patients presented with a rash; nearly 75% had anogenital lesions; and 41%, 25%, and 10% had involvement of mucosae, the face, and palms/soles, respectively. More than half of patients had fewer than 10 lesions, and 10% presented with a single genital lesion.¹⁹

Given the recent predilection of lesions for the anogenital area, the differential diagnosis of mpox should include other common infections localized to these areas. Unlike herpes simplex and varicella-zoster infections, mpox does not exhibit the classic herpetiform clustering of vesicles, and unlike the painless chancre of syphilis, the lesions of mpox are exquisitely painful. Similar to chancroid, mpox presents with painful genital lesions and lymphadenopathy, and the umbilicated papules of molluscum could easily be confused with mpox lesions. Proctitis caused by many sexually transmitted infections (STIs), including chlamydia and gonorrhea, may be difficult to differentiate from proctitis symptoms of mpox. Co-infection with HIV and other STIs is common among patients developing mpox in 2022, which is not surprising given that the primary mechanism of transmission of mpox at this time is through sexual contact, and cases are more common in patients with multiple recent sexual partners.¹⁹ Considering these shared risk factors and similar presentation of multiple STIs, patients suspected of having an mpox infection should be tested for other STIs, including HIV.

Complications of Mpox

Although mpox generally is characterized by a mild disease course, there is concern for adverse outcomes, particularly in more vulnerable populations, including immunocompromised, pregnant, and pediatric populations. Complications of infection can include sepsis, encephalitis, bronchopneumonia, and ophthalmic complications that can result in loss of vision.^6,17 The most common complications requiring hospitalization in a recent international report of 528 mpox cases were pain management, which was primarily due to severe anogenital pain, followed by soft-tissue superinfection, with other complications including severe pharyngitis limiting oral intake and infection control practices.¹⁹ In addition to severe rectal pain, proctitis and even rectal perforation have been reported.^19,20

Vertical transmission has been described with devastating outcomes in a case series from the Democratic Republic of Congo, where 4 cases of mpox were identified in pregnant women; 3 of these pregnancies resulted in fetal demise.¹⁰ The only fetus to survive was born to a mother with mild infection. In comparison, 2 of 3 mothers with moderate to severe disease experienced spontaneous abortion in the first trimester, and 1 pregnancy ended due to intrauterine demise during the eighteenth week of gestation, likely a complication of mpox. These cases suggest that more severe disease may be linked to worse fetal outcomes.¹⁰ Further epidemiologic studies will be crucial, given the potential implications.

Diagnosis

When considering a diagnosis of mpox, clinicians should inquire about recent travel, living arrangements, sexual history, and recent sick contacts.⁶ A complete skin examination should include the oral and genital areas, given the high prevalence of lesions in these areas. A skin biopsy is not recommended for the diagnosis of mpox, as nonspecific viral changes cannot be differentiated from other viral exanthems, but it often is useful to rule out other differential diagnoses.²¹ Additionally, immunohistochemistry and electron microscopy can be utilized to aid in a histologic diagnosis of mpox.

Polymerase chain reaction detection of orthopox or mpox DNA is the gold standard for diagnosis.⁶ Two swabs should be collected from each lesion by swabbing vigorously using sterile swabs made of a synthetic material such as polyester, nylon, or Dacron and placed into a sterile container or viral transport medium.²² Some laboratories may have different instructions for collection of samples, so clinicians are advised to check for instructions from their local laboratory. Deroofing lesions prior to swabbing is not necessary, and specimens can include lesional material or crust. Collection of specimens from 2 to 3 lesions is recommended, preferably from different body areas or lesions with varying morphologies. Anal or rectal swabs can be considered in patients presenting with anal pain or proctitis with clinical suspicion for mpox based on history.¹⁹

Infection Prevention

Interim guidance from the WHO on November 16, 2022, reiterated the goal of outbreak control primarily via public health measures, which includes targeted use of vaccines for at-risk populations or postexposure prophylactic vaccination within 4 days, but heavily relies on surveillance and containment techniques, such as contact tracing with monitoring of contacts for onset of symptoms and isolation of cases through the complete infectious period.²³ Patients are considered infectious from symptom onset until all cutaneous lesions are re-epithelized and should remain in isolation, including from household contacts and domestic and wildlife animals, for the duration of illness.^24,25 Individuals exposed to humans or animals with confirmed mpox should be monitored for the development of symptoms for 21 days following last known exposure, regardless of vaccination status, and should be instructed to measure their temperature twice daily.²⁶ Pets exposed to mpox should be isolated from other animals and humans for 21 days following last known contact.²⁴ Vaccination strategies for preexposure and postexposure prophylaxis (PEP) are discussed below in further detail. Postinfection, the WHO suggests use of condoms for all oral, vaginal, and anal sexual activity for 12 weeks after recovery.⁷

Patients with suspected or confirmed mpox in a hospital should be in a single private room on special droplet and contact precautions.²⁷ No special air handling or negative pressure isolation is needed unless the patient is undergoing an aerosol-generating procedure (eg, intubation, endoscopy, bronchoscopy). When hospitalized, patients should have a dedicated bathroom, if possible, and at-home patients should be isolated from household members until contagion risk resolves; this includes the use of a separate bathroom, when possible. Health care personnel entering the room of a patient should don appropriate personal protective equipment (PPE), including a disposable gown, gloves, eye protection, and N95 respirator or equivalent. Recommendations include standard practices for cleaning, with wet cleaning methods preferred over dry methods, using a disinfectant that covers emerging viral pathogens, and avoidance of shaking linens to prevent the spread of infectious particles.²⁷ A variety of Environmental Protection Agency–registered wipes with virucidal activity against emerging viruses, including those with active ingredients such as quaternary ammonium, hydrogen peroxide, and hypochlorous acid, should be used for disinfecting surfaces.²⁸

Vaccination

ACAM2000 (Emergent Bio Solutions) and JYNNEOS (Bavarian Nordic)(also known as Imvamune or Imvanex) are available in the United States for the prevention of mpox infection.²⁹ ACAM2000, a second-generation, replication-competent, live smallpox vaccine administered as a single percutaneous injection, is contraindicated in immunocompromised populations, including patients with HIV or on immunosuppressive or biologic therapy, pregnant individuals, people with a history of atopic dermatitis or other exfoliative skin diseases with impaired barrier function, and patients with a history of cardiac disease due to the risk of myocarditis and pericarditis.³⁰

JYNNEOS is a nonreplicating live vaccine approved by the US Food and Drug Administration (FDA) for the prevention of mpox in individuals older than 18 years administered as 2 subcutaneous doses 4 weeks apart. Patients are considered fully vaccinated 2 weeks after the second dose, and JYNNEOS is available to pediatric patients with a single patient expanded access use authorization from the FDA.^29,30 More recently, the FDA issued an emergency use authorization (EUA) for administration of the vaccine to patients younger than 18 years who are at high risk of infection after exposure.³¹ More importantly, the FDA also issued an EUA for the intradermal administration of JYNNEOS at one-fifth of the subcutaneous dose to expand the current vaccine supply. This EUA is based on research by Frey et al,³² which showed that intradermal administration, even at a lower dose, elicited similar immune responses among study participants as the higher dose administered subcutaneously.

JYNNEOS is the preferred vaccine for the prevention of mpox because of its poor ability to replicate in human cells and resultant safety for use in populations that are immunocompromised, pregnant, or have skin barrier defects such as atopic dermatitis, without the risk of myocarditis or pericarditis. However, current supplies are limited. JYNNEOS was specifically studied in patients with atopic dermatitis and has been shown to be safe and effective in patients with a history of atopic dermatitis and active disease with a SCORAD (SCORing Atopic Dermatitis) score of 30 or lower.³³ Of note, JYNNEOS is contraindicated in patients allergic to components of the vaccine, including egg, gentamicin, and ciprofloxacin. Although JYNNEOS is safe to administer to persons with immunocompromising conditions, the CDC reports that such persons might be at increased risk for severe disease if an occupational infection occurs, and in the setting of immunocompromise, such persons may be less likely to mount an effective response to vaccination. Therefore, the risk-benefit ratio should be considered to determine if an immunocompromised person should be vaccinated with JYNNEOS.³⁰

The WHO and the CDC do not recommended mass vaccination of the general public for outbreaks of mpox in nonendemic countries, with immunization reserved for appropriate PEP and pre-exposure prophylaxis in intermediate- to high-risk individuals.^23,26 The CDC recommends PEP vaccination for individuals with a high degree of exposure that includes unprotected contact of the skin or mucous membranes of an individual to the skin, lesions, body fluids, or contaminated fomites from a patient with mpox, as well as being within 6 feet of a patient during an aerosolization procedure without proper PPE. Following an intermediate degree of exposure, which includes being within 6 feet for 3 or more hours wearing at minimum a surgical mask or contact with fomites while wearing incomplete PPE, the CDC recommends monitoring and shared decision-making regarding risks and benefits of PEP vaccination. Monitoring without PEP is indicated for low and uncertain degrees of exposure, including entering a room without full PPE such as eye protection, regardless of the duration of contact.^23,26

Postexposure prophylaxis vaccination should be administered within 4 days of a known high-level exposure to mpox to prevent infection.²⁹ If administered within 4 to 14 days postexposure, vaccination may reduce disease severity but will not prevent infection.³⁴

Pre-exposure prophylaxis is recommended for individuals at high risk for exposure to mpox, including health care workers such as laboratory personnel who handle mpox specimens and health care workers who administer ACAM2000 vaccinations or anticipate providing care for many patients with mpox.³⁴

Management

Most cases of mpox are characterized by mild to moderate disease with a self-limited course. Most commonly, medical management of mpox involves supportive care such as fluid resuscitation, supplemental oxygen, and pain management.⁶ Treatment of superinfected skin lesions may require antibiotics. In the event of ophthalmologic involvement, patients should be referred to an ophthalmologist for further management.

Currently, there are no FDA-approved therapies for mpox; however, tecovirimat, cidofovir, brincidofovir, and vaccinia immune globulin intravenous are available under expanded access Investigational New Drug protocols.^6,35 Human data for cidofovir, brincidofovir, and vaccinia immune globulin intravenous in the treatment of mpox are lacking, while cidofovir and brincidofovir have shown efficacy against orthopoxviruses in in vitro and animal studies, but are available therapeutic options.³⁵

Tecovirimat is an antiviral that is FDA approved for smallpox with efficacy data against mpox in animal studies. It is the first-line treatment for patients with severe disease requiring hospitalization or 1 or more complications, including dehydration or secondary skin infections, as well as for populations at risk for severe disease, which includes immunocompromised patients, pediatric patients younger than 8 years, pregnant or breastfeeding individuals, or patients with a history of atopic dermatitis or active exfoliative skin conditions.³⁶ In this current outbreak, both intravenous and oral tecovirimat are weight based in adult and pediatric patients for 14 days, with the intravenous form dosed every 12 hours by infusion over 6 hours, and the oral doses administered every 8 to 12 hours based on patient weight.³⁷ Tecovirimat generally is well tolerated with mild side effects but is notably contraindicated in patients with severe renal impairment with a creatinine clearance less than 30 mL/min, and renal monitoring is indicated in pediatric patients younger than 2 years and in all patients receiving intravenous treatment.

Conclusion

Given that cutaneous lesions are the most specific presenting sign of mpox infection, dermatologists will play an integral role in identifying future cases and managing future outbreaks. Mpox should be considered in the differential diagnosis for all patients presenting with umbilicated or papulovesicular lesions, particularly in an anogenital distribution. The classic presentation of mpox may be more common among patients who are not considered high risk and have not been exposed via sexual activity. All patients with suspicious lesions should be managed following appropriate infection control precautions and should undergo molecular diagnostic assay of swabbed lesions to confirm the diagnosis. JYNNEOS is the only vaccine that is currently being distributed in the United States and is safe to administer to immunocompromised populations. The risks and benefits of vaccination should be considered on an individual basis between a patient and their provider. Taking into consideration that patients with atopic dermatitis are at risk for severe disease if infected with mpox, vaccination should be strongly encouraged if indicated based on patient risk factors. For atopic dermatitis patients treated with dupilumab, shared decision-making is essential given the FDA label, which recommends avoiding the use of live vaccines.³⁸

The mpox epidemic occurring amidst the ongoing COVID-19 pandemic should serve as a wake-up call to the importance of pandemic preparedness and the global health response strategies in the modern era of globalization. Looking forward, widespread vaccination against mpox may be necessary to control the spread of the disease and to protect vulnerable populations, including pregnant individuals. In the current climate of hesitancy surrounding vaccines and the erosion of trust in public health agencies, it is incumbent upon health care providers to educate patients regarding the role of vaccines and public health measures to control this developing global health crisis.

Practice Gap

Skin picking disorder is characterized by repetitive deliberate manipulation of the skin that causes noticeable tissue damage. It affects approximately 1.6% of adults in the United States and is associated with marked distress as well as a psychosocial impact.¹ Complications of skin picking disorder can include ulceration, infection, scarring, and disfigurement.

Cognitive behavioral therapy (CBT) techniques have been established to be effective in treating skin picking disorder.² Although referral to a mental health professional is appropriate for patients with skin picking disorder, many of them may not be interested. Cognitive behavioral therapy for diseases at the intersection of psychiatry and dermatology typically is not included in dermatology curricula. Therefore, dermatologists should be aware of CBT techniques that can mitigate the impact of skin picking disorder for patients who decline referral to a mental health professional.

The Technique

Cognitive behavioral therapy is one of the more effective forms of psychotherapy for the treatment of skin picking disorder. Consistent utilization of CBT techniques can achieve relatively permanent change in brain function and contribute to long-term treatment outcomes. A particularly useful CBT technique for skin picking disorder is habit reversal therapy (HRT)(Table). Studies have shown that HRT techniques have demonstrated efficacy in skin picking disorder with sustained impact.³ Patients treated with HRT have reported a greater decrease in skin picking compared with controls after only 3 sessions (P<.01).⁴ There are 3 elements to HRT:

1. Sensitization and awareness training: This facet of HRT involves helping the patient become attuned to warning signals, or feelings, that precede their skin picking, as skin picking often occurs automatically without the patient noticing. Such feelings can include tingling of the skin, tension, and a feeling of being overwhelmed.⁵ Ideally, the physician works with the patient to identify 2 or 3 warning signals that precede skin picking behavior.

2. Competing response training: The patient is encouraged to substitute skin picking with a preventive behavior—for example, crossing the arms and gently squeezing the fists—that is incompatible with skin picking. The preventive behavior should be performed for at least 1 minute as soon as a warning signal appears or skin picking behavior starts. After 1 minute, if the urge for skin picking recurs, then the patient should repeat the preventive behavior.⁵ It can be helpful to practice the preventive behavior with the patient once in the clinic.

3. Social support: This technique involves identifying a close social contact of the patient (eg, relative, friend, partner) to help the patient increase their awareness of skin picking behavior and encourage them to perform the preventive behavior.⁵ The purpose of identifying a close social contact is to ensure accountability for the patient in their day-to-day life, given the limited scope of the relationship between the patient and the dermatologist.

Other practical solutions to skin picking include advising patients to cut their nails short; using finger cots to cover the nails and thus lessen the potential for skin injury; and using a sensory toy, such as a fidget spinner, to distract or occupy the patient when they feel the urge for skin picking.

Practice Implications

Although skin picking disorder is a challenging condition to manage, there are proven techniques for treatment. Techniques drawn from HRT are quite practical and can be implemented by dermatologists for patients with skin picking disorder to reduce the burden of their disease.

Practice Gap

Skin picking disorder is characterized by repetitive deliberate manipulation of the skin that causes noticeable tissue damage. It affects approximately 1.6% of adults in the United States and is associated with marked distress as well as a psychosocial impact.¹ Complications of skin picking disorder can include ulceration, infection, scarring, and disfigurement.

Cognitive behavioral therapy (CBT) techniques have been established to be effective in treating skin picking disorder.² Although referral to a mental health professional is appropriate for patients with skin picking disorder, many of them may not be interested. Cognitive behavioral therapy for diseases at the intersection of psychiatry and dermatology typically is not included in dermatology curricula. Therefore, dermatologists should be aware of CBT techniques that can mitigate the impact of skin picking disorder for patients who decline referral to a mental health professional.

The Technique

Cognitive behavioral therapy is one of the more effective forms of psychotherapy for the treatment of skin picking disorder. Consistent utilization of CBT techniques can achieve relatively permanent change in brain function and contribute to long-term treatment outcomes. A particularly useful CBT technique for skin picking disorder is habit reversal therapy (HRT)(Table). Studies have shown that HRT techniques have demonstrated efficacy in skin picking disorder with sustained impact.³ Patients treated with HRT have reported a greater decrease in skin picking compared with controls after only 3 sessions (P<.01).⁴ There are 3 elements to HRT:

1. Sensitization and awareness training: This facet of HRT involves helping the patient become attuned to warning signals, or feelings, that precede their skin picking, as skin picking often occurs automatically without the patient noticing. Such feelings can include tingling of the skin, tension, and a feeling of being overwhelmed.⁵ Ideally, the physician works with the patient to identify 2 or 3 warning signals that precede skin picking behavior.

2. Competing response training: The patient is encouraged to substitute skin picking with a preventive behavior—for example, crossing the arms and gently squeezing the fists—that is incompatible with skin picking. The preventive behavior should be performed for at least 1 minute as soon as a warning signal appears or skin picking behavior starts. After 1 minute, if the urge for skin picking recurs, then the patient should repeat the preventive behavior.⁵ It can be helpful to practice the preventive behavior with the patient once in the clinic.

3. Social support: This technique involves identifying a close social contact of the patient (eg, relative, friend, partner) to help the patient increase their awareness of skin picking behavior and encourage them to perform the preventive behavior.⁵ The purpose of identifying a close social contact is to ensure accountability for the patient in their day-to-day life, given the limited scope of the relationship between the patient and the dermatologist.

Other practical solutions to skin picking include advising patients to cut their nails short; using finger cots to cover the nails and thus lessen the potential for skin injury; and using a sensory toy, such as a fidget spinner, to distract or occupy the patient when they feel the urge for skin picking.

Practice Implications

Although skin picking disorder is a challenging condition to manage, there are proven techniques for treatment. Techniques drawn from HRT are quite practical and can be implemented by dermatologists for patients with skin picking disorder to reduce the burden of their disease.

Practice Gap

Skin picking disorder is characterized by repetitive deliberate manipulation of the skin that causes noticeable tissue damage. It affects approximately 1.6% of adults in the United States and is associated with marked distress as well as a psychosocial impact.¹ Complications of skin picking disorder can include ulceration, infection, scarring, and disfigurement.

Cognitive behavioral therapy (CBT) techniques have been established to be effective in treating skin picking disorder.² Although referral to a mental health professional is appropriate for patients with skin picking disorder, many of them may not be interested. Cognitive behavioral therapy for diseases at the intersection of psychiatry and dermatology typically is not included in dermatology curricula. Therefore, dermatologists should be aware of CBT techniques that can mitigate the impact of skin picking disorder for patients who decline referral to a mental health professional.

The Technique

Cognitive behavioral therapy is one of the more effective forms of psychotherapy for the treatment of skin picking disorder. Consistent utilization of CBT techniques can achieve relatively permanent change in brain function and contribute to long-term treatment outcomes. A particularly useful CBT technique for skin picking disorder is habit reversal therapy (HRT)(Table). Studies have shown that HRT techniques have demonstrated efficacy in skin picking disorder with sustained impact.³ Patients treated with HRT have reported a greater decrease in skin picking compared with controls after only 3 sessions (P<.01).⁴ There are 3 elements to HRT:

1. Sensitization and awareness training: This facet of HRT involves helping the patient become attuned to warning signals, or feelings, that precede their skin picking, as skin picking often occurs automatically without the patient noticing. Such feelings can include tingling of the skin, tension, and a feeling of being overwhelmed.⁵ Ideally, the physician works with the patient to identify 2 or 3 warning signals that precede skin picking behavior.

2. Competing response training: The patient is encouraged to substitute skin picking with a preventive behavior—for example, crossing the arms and gently squeezing the fists—that is incompatible with skin picking. The preventive behavior should be performed for at least 1 minute as soon as a warning signal appears or skin picking behavior starts. After 1 minute, if the urge for skin picking recurs, then the patient should repeat the preventive behavior.⁵ It can be helpful to practice the preventive behavior with the patient once in the clinic.

3. Social support: This technique involves identifying a close social contact of the patient (eg, relative, friend, partner) to help the patient increase their awareness of skin picking behavior and encourage them to perform the preventive behavior.⁵ The purpose of identifying a close social contact is to ensure accountability for the patient in their day-to-day life, given the limited scope of the relationship between the patient and the dermatologist.

Other practical solutions to skin picking include advising patients to cut their nails short; using finger cots to cover the nails and thus lessen the potential for skin injury; and using a sensory toy, such as a fidget spinner, to distract or occupy the patient when they feel the urge for skin picking.

Practice Implications

Although skin picking disorder is a challenging condition to manage, there are proven techniques for treatment. Techniques drawn from HRT are quite practical and can be implemented by dermatologists for patients with skin picking disorder to reduce the burden of their disease.

The Diagnosis: Porokeratosis Plantaris Palmaris et Disseminata

A 3-mm punch biopsy of the right upper arm showed incipient cornoid lamellae formation, pigment incontinence, and sparse dermal lymphocytic inflammation (Figure), suggestive of porokeratosis plantaris palmaris et disseminata (PPPD). The dermatopathologist recommended a second biopsy to confirm the diagnosis and to confirm that the lesions on the palms and soles also were suggestive of porokeratosis. A second 4-mm punch biopsy of the left palm was consistent with PPPD.

The risks of PPPD as a precancerous entity along with the benefits and side effects of the various management options were discussed with our patient. We recommended that he start low-dose isotretinoin (20 mg/d) due to the large body surface area affected, making focal and field treatments likely insufficient. However, our patient opted not to treat and did not return for follow-up.

Subtypes of porokeratosis, including disseminated superficial actinic porokeratosis (DSAP) and PPPD, are conditions that disrupt the normal maturation of keratin and present clinically with symmetric, crusted, annular papules.¹ The signature but nonspecific histopathologic feature shared among the subtypes is the presence of a cornoid lamellae.² Several triggers of porokeratosis have been proposed, including trauma and exposure to UV and ionizing radiation.^2,3 The clinical variants of porokeratosis are important conditions to diagnose correctly because they portend a risk for Bowen disease and invasive squamous cell carcinoma and may indicate the presence of an underlying hematologic and/or solid organ malignancy.⁴ Management of porokeratosis is difficult, as treatments have shown limited efficacy and variable recurrence rates. Treatment options include focal, field, and systemic options, such as 5-fluorouracil, topical compound of cholesterol and lovastatin, isotretinoin, and acitretin.^1,2

Porokeratoses may arise from gene mutations in the mevalonate pathway,⁵ which is essential for the production of cholesterol.⁶ Topical cholesterol alone has not been shown to improve porokeratosis, but the combination topical therapy of cholesterol and lovastatin is promising. It is theorized to deliver benefit by both providing the essential end product of the pathway and simultaneously reducing the number of potentially toxic intermediates.⁶

Porokeratosis plantaris palmaris et disseminata (also known as porokeratosis plantaris) is unique among the subtypes of porokeratosis in that its annular, red-pink, papular rash with scaling and a keratotic border tends to start distally, involving the palms and soles, and progresses proximally to the trunk with smaller lesions.^1,7 This centripetal progression can take years, as was seen in our patient.¹ The disease is uncommon, with a dearth of published reports on PPPD.² However, case reports have shown that PPPD is strongly linked to family history and may have an autosomal-dominant inheritance pattern. Penetrance is greater in men than in women, as PPPD is twice as common in men.⁸ Most cases of PPPD have been diagnosed in patients in their 20s and 30s, but Hartman et al9 reported a case wherein a patient was diagnosed with PPPD after 65 years of age, similar to our patient.

Although the lesions in DSAP can appear similar to those in PPPD, DSAP is more common among the family of porokeratotic conditions, affecting women twice as often as men, with a sporadic pattern of inheritance.² These same features are present in some other types of porokeratosis but not PPPD. Furthermore, DSAP progresses proximally to distally but often with truncal sparing.²

Akin to PPPD, pityriasis rubra pilaris (PRP) often presents with palmoplantar keratoderma.¹⁰ There are at least 6 types of PRP with varying degrees of similarity to PPPD. However, in many cases PRP is associated with a background of diffuse erythema on the body with islands of spared skin. In addition, cases of PRP have been linked to extracutaneous findings such as ectropion and joint pain.¹¹

Darier disease, especially the acrokeratosis verruciformis of Hopf variant, is more common in men and involves younger populations, as in PPPD.¹¹ However, the crusted lesions seen in Darier disease frequently involve the skin folds. These intertriginous lesions may coalesce, mimicking warts in appearance, and are at risk for secondary infection. Nail findings in Darier disease also are distinct and include longitudinal white or red stripes running along the nail bed, in addition to V-shaped nicks at the nail tips.

Psoriasis can occur anywhere on the body and is associated with silver scaling atop a salmon-colored dermatitis.¹² It results from aberrant proliferation of keratinocytes. Some distinguishing features of psoriasis include a disease course that waxes and wanes as well as pitting of the nails.

Although PPPD typically affects young adults, we presented a case of PPPD in an older man. Porokeratosis plantaris palmaris et disseminata in older adults may represent a delayed diagnosis, imply a broader range for the age of onset, or suggest its manifestation secondary to radiation treatment or another phenomenon. For example, our patient received 35 radiotherapy cycles for tongue cancer more than 5 years prior to the onset of PPPD.

The Diagnosis: Porokeratosis Plantaris Palmaris et Disseminata

A 3-mm punch biopsy of the right upper arm showed incipient cornoid lamellae formation, pigment incontinence, and sparse dermal lymphocytic inflammation (Figure), suggestive of porokeratosis plantaris palmaris et disseminata (PPPD). The dermatopathologist recommended a second biopsy to confirm the diagnosis and to confirm that the lesions on the palms and soles also were suggestive of porokeratosis. A second 4-mm punch biopsy of the left palm was consistent with PPPD.

The risks of PPPD as a precancerous entity along with the benefits and side effects of the various management options were discussed with our patient. We recommended that he start low-dose isotretinoin (20 mg/d) due to the large body surface area affected, making focal and field treatments likely insufficient. However, our patient opted not to treat and did not return for follow-up.

Subtypes of porokeratosis, including disseminated superficial actinic porokeratosis (DSAP) and PPPD, are conditions that disrupt the normal maturation of keratin and present clinically with symmetric, crusted, annular papules.¹ The signature but nonspecific histopathologic feature shared among the subtypes is the presence of a cornoid lamellae.² Several triggers of porokeratosis have been proposed, including trauma and exposure to UV and ionizing radiation.^2,3 The clinical variants of porokeratosis are important conditions to diagnose correctly because they portend a risk for Bowen disease and invasive squamous cell carcinoma and may indicate the presence of an underlying hematologic and/or solid organ malignancy.⁴ Management of porokeratosis is difficult, as treatments have shown limited efficacy and variable recurrence rates. Treatment options include focal, field, and systemic options, such as 5-fluorouracil, topical compound of cholesterol and lovastatin, isotretinoin, and acitretin.^1,2

Porokeratoses may arise from gene mutations in the mevalonate pathway,⁵ which is essential for the production of cholesterol.⁶ Topical cholesterol alone has not been shown to improve porokeratosis, but the combination topical therapy of cholesterol and lovastatin is promising. It is theorized to deliver benefit by both providing the essential end product of the pathway and simultaneously reducing the number of potentially toxic intermediates.⁶

Porokeratosis plantaris palmaris et disseminata (also known as porokeratosis plantaris) is unique among the subtypes of porokeratosis in that its annular, red-pink, papular rash with scaling and a keratotic border tends to start distally, involving the palms and soles, and progresses proximally to the trunk with smaller lesions.^1,7 This centripetal progression can take years, as was seen in our patient.¹ The disease is uncommon, with a dearth of published reports on PPPD.² However, case reports have shown that PPPD is strongly linked to family history and may have an autosomal-dominant inheritance pattern. Penetrance is greater in men than in women, as PPPD is twice as common in men.⁸ Most cases of PPPD have been diagnosed in patients in their 20s and 30s, but Hartman et al9 reported a case wherein a patient was diagnosed with PPPD after 65 years of age, similar to our patient.

Although the lesions in DSAP can appear similar to those in PPPD, DSAP is more common among the family of porokeratotic conditions, affecting women twice as often as men, with a sporadic pattern of inheritance.² These same features are present in some other types of porokeratosis but not PPPD. Furthermore, DSAP progresses proximally to distally but often with truncal sparing.²

Akin to PPPD, pityriasis rubra pilaris (PRP) often presents with palmoplantar keratoderma.¹⁰ There are at least 6 types of PRP with varying degrees of similarity to PPPD. However, in many cases PRP is associated with a background of diffuse erythema on the body with islands of spared skin. In addition, cases of PRP have been linked to extracutaneous findings such as ectropion and joint pain.¹¹

Darier disease, especially the acrokeratosis verruciformis of Hopf variant, is more common in men and involves younger populations, as in PPPD.¹¹ However, the crusted lesions seen in Darier disease frequently involve the skin folds. These intertriginous lesions may coalesce, mimicking warts in appearance, and are at risk for secondary infection. Nail findings in Darier disease also are distinct and include longitudinal white or red stripes running along the nail bed, in addition to V-shaped nicks at the nail tips.

Psoriasis can occur anywhere on the body and is associated with silver scaling atop a salmon-colored dermatitis.¹² It results from aberrant proliferation of keratinocytes. Some distinguishing features of psoriasis include a disease course that waxes and wanes as well as pitting of the nails.

Although PPPD typically affects young adults, we presented a case of PPPD in an older man. Porokeratosis plantaris palmaris et disseminata in older adults may represent a delayed diagnosis, imply a broader range for the age of onset, or suggest its manifestation secondary to radiation treatment or another phenomenon. For example, our patient received 35 radiotherapy cycles for tongue cancer more than 5 years prior to the onset of PPPD.

The Diagnosis: Porokeratosis Plantaris Palmaris et Disseminata

A 3-mm punch biopsy of the right upper arm showed incipient cornoid lamellae formation, pigment incontinence, and sparse dermal lymphocytic inflammation (Figure), suggestive of porokeratosis plantaris palmaris et disseminata (PPPD). The dermatopathologist recommended a second biopsy to confirm the diagnosis and to confirm that the lesions on the palms and soles also were suggestive of porokeratosis. A second 4-mm punch biopsy of the left palm was consistent with PPPD.

The risks of PPPD as a precancerous entity along with the benefits and side effects of the various management options were discussed with our patient. We recommended that he start low-dose isotretinoin (20 mg/d) due to the large body surface area affected, making focal and field treatments likely insufficient. However, our patient opted not to treat and did not return for follow-up.

Subtypes of porokeratosis, including disseminated superficial actinic porokeratosis (DSAP) and PPPD, are conditions that disrupt the normal maturation of keratin and present clinically with symmetric, crusted, annular papules.¹ The signature but nonspecific histopathologic feature shared among the subtypes is the presence of a cornoid lamellae.² Several triggers of porokeratosis have been proposed, including trauma and exposure to UV and ionizing radiation.^2,3 The clinical variants of porokeratosis are important conditions to diagnose correctly because they portend a risk for Bowen disease and invasive squamous cell carcinoma and may indicate the presence of an underlying hematologic and/or solid organ malignancy.⁴ Management of porokeratosis is difficult, as treatments have shown limited efficacy and variable recurrence rates. Treatment options include focal, field, and systemic options, such as 5-fluorouracil, topical compound of cholesterol and lovastatin, isotretinoin, and acitretin.^1,2

Porokeratoses may arise from gene mutations in the mevalonate pathway,⁵ which is essential for the production of cholesterol.⁶ Topical cholesterol alone has not been shown to improve porokeratosis, but the combination topical therapy of cholesterol and lovastatin is promising. It is theorized to deliver benefit by both providing the essential end product of the pathway and simultaneously reducing the number of potentially toxic intermediates.⁶

Porokeratosis plantaris palmaris et disseminata (also known as porokeratosis plantaris) is unique among the subtypes of porokeratosis in that its annular, red-pink, papular rash with scaling and a keratotic border tends to start distally, involving the palms and soles, and progresses proximally to the trunk with smaller lesions.^1,7 This centripetal progression can take years, as was seen in our patient.¹ The disease is uncommon, with a dearth of published reports on PPPD.² However, case reports have shown that PPPD is strongly linked to family history and may have an autosomal-dominant inheritance pattern. Penetrance is greater in men than in women, as PPPD is twice as common in men.⁸ Most cases of PPPD have been diagnosed in patients in their 20s and 30s, but Hartman et al9 reported a case wherein a patient was diagnosed with PPPD after 65 years of age, similar to our patient.

Although the lesions in DSAP can appear similar to those in PPPD, DSAP is more common among the family of porokeratotic conditions, affecting women twice as often as men, with a sporadic pattern of inheritance.² These same features are present in some other types of porokeratosis but not PPPD. Furthermore, DSAP progresses proximally to distally but often with truncal sparing.²

Akin to PPPD, pityriasis rubra pilaris (PRP) often presents with palmoplantar keratoderma.¹⁰ There are at least 6 types of PRP with varying degrees of similarity to PPPD. However, in many cases PRP is associated with a background of diffuse erythema on the body with islands of spared skin. In addition, cases of PRP have been linked to extracutaneous findings such as ectropion and joint pain.¹¹

Darier disease, especially the acrokeratosis verruciformis of Hopf variant, is more common in men and involves younger populations, as in PPPD.¹¹ However, the crusted lesions seen in Darier disease frequently involve the skin folds. These intertriginous lesions may coalesce, mimicking warts in appearance, and are at risk for secondary infection. Nail findings in Darier disease also are distinct and include longitudinal white or red stripes running along the nail bed, in addition to V-shaped nicks at the nail tips.

Psoriasis can occur anywhere on the body and is associated with silver scaling atop a salmon-colored dermatitis.¹² It results from aberrant proliferation of keratinocytes. Some distinguishing features of psoriasis include a disease course that waxes and wanes as well as pitting of the nails.

Although PPPD typically affects young adults, we presented a case of PPPD in an older man. Porokeratosis plantaris palmaris et disseminata in older adults may represent a delayed diagnosis, imply a broader range for the age of onset, or suggest its manifestation secondary to radiation treatment or another phenomenon. For example, our patient received 35 radiotherapy cycles for tongue cancer more than 5 years prior to the onset of PPPD.

Diversity of health care professionals improves medical outcomes and quality of life in patients. ¹ There is a lack of diversity in dermatology, with only 4.2% of dermatologists identifying as Hispanic and 3% identifying as African American, ² possibly due to a lack of early exposure to dermatology among high school and undergraduate students, a low number of underrepresented students in medical school, a lack of formal mentorship programs geared to underrepresented students, and implicit biases. ^1-4 Furthermore, the field is competitive, with many more applicants than available positions. In 2022, there were 851 applicants competing for 492 residency positions in dermatology. ⁵ Thus, it is important to educate young students about dermatology and understand root causes as to why the number of u nderrepresented in medicine (UiM) dermatologists remains stagnant.

According to Pritchett et al,⁴ it is crucial for dermatologists to interact with high school and college students to foster an early interest in dermatology. Many racial minority students do not progress from high school to college and then from college to medical school, which leaves a substantially reduced number of eligible UiM applicants who can progress into dermatology.⁶ Increasing the amount of UiM students going to medical school requires early mediation. Collaborating with pre-existing premedical school organizations through presentations and workshops is another way to promote an early interest in dermatology.⁴ Special consideration should be given to students who are UiM.

Among the general medical school curriculum, requirements for exposure to dermatology are not high. In one study, the median number of clinical and preclinical hours required was 10. Furthermore, 20% of 33 medical schools did not require preclinical dermatology hours (hours done before medical school rotations begin and in an academic setting), 36% required no clinical hours (rotational hours), 8% required no dermatology hours whatsoever, and only 10% required clinical dermatology rotation.³ Based on these findings, it is clear that dermatology is not well incorporated into medical school curricula. Furthermore, curricula have historically neglected to display adequate representation of skin of color.⁷ As a result, medical students generally have limited exposure to dermatology³ and are exposed even less to presentations of dermatologic issues in historically marginalized populations.⁷

Given the paucity of research on UiM students’ perceptions of dermatology prior to medical school, our cross-sectional survey study sought to evaluate the level of interest in dermatology of UiM premedical undergraduates. This survey specifically evaluated exposure to dermatology, preconceived notions about the field, and mentorship opportunities. By understanding these factors, dermatologists and dermatology residency programs can use this information to create mentorship opportunities and better adjust existing programs to meet students’ needs.

Methods

A 19-question multiple-choice survey was administered electronically (SurveyMonkey) in May 2020 to premedical students at Howard University (Washington, DC). One screening question was used: “What is your major?” Those who considered themselves a science major and/or with premedical interest were allowed to complete the survey. All students surveyed were members of the Health Professions Society at Howard University. Students who were interested in pursuing medical school were invited to respond. Approval for this study was obtained from the Howard University institutional review board (FWA00000891).

The survey was divided into 3 sections: Demographics, Exposure to Medicine and Dermatology, and Perceptions of Dermatology. The Demographics section addressed gender, age, and race/ethnicity. The Exposure to Medicine and Dermatology section addressed interest in attending medical school, shadowing experience, exposure to dermatology, and mentoring. The Perceptions of Dermatology section addressed preconceived notions about the field (eg, “dermatology is interesting and exciting”).

Statistical Analysis—The data represented are percentages based on the number of respondents who answered each question. Answers in response to “Please enter any comments” were organized into themes, and the number of respondents who discussed each theme was quantified into a table.

A total of 271 survey invitations were sent to premedical students at Howard University. Students were informed of the study protocol and asked to consent before proceeding to have their responses anonymously collected. Based on the screening question, 152 participants qualified for the survey, and 152 participants completed it (response rate, 56%; completion rate, 100%). Participants were asked to complete the survey only once.

Demographics—Eighty-four percent of respondents identified as science majors, and the remaining 16% identified as nonscience premedical. Ninety-four percent of participants identified as Black or African American; 3% as Asian or Asian American; and the remaining 3% as Other. Most respondents were female (82%), 16% were male, and 2% were either nonbinary or preferred not to answer. Ninety-nine percent were aged 18 to 24 years, and 1% were aged 25 to 34 years (Table 1).

Exposure to Medicine and Dermatology—Ninety-three percent of participants planned on attending medical school, and most students developed an interest in medicine from an early age. Ninety-six percent cited that they became interested in medicine prior to beginning their undergraduate education, and 4% developed an interest as freshmen or sophomores. When asked what led to their interest in medicine, family influence had the single greatest impact on students’ decision to pursue medicine (33%). Classes/school were the second most influential factor (24%), followed by volunteering (15%), shadowing (13%), other (7%), and peer influence (3%)(Figure 1).

Many (56%) premedical students surveyed had shadowing experience to varying degrees. Approximately 18% had fewer than 8 hours of shadowing experience, 24% had 8 to 40 hours, and 14% had more than 40 hours. However, many (43%) premedical students had no shadowing experience (Figure 2). Similarly, 30% of premedical students responded to having a physician as a mentor.

Regarding exposure to dermatology, 42% of premedical students had none. However, 58% of students had exposure to dermatology by being a patient themselves, 40% through seeing a dermatologist with a family member, 21% through seeing a dermatologist on television or social media, 5% through shadowing or volunteering, 3% through mentorship, and 1% through dermatology research (Figure 3).

Of students who said they were interested in dermatology (32%), 16% developed their interest before undergraduate education, while 9% developed interest in their freshman or sophomore year and 7% in their junior or senior year of undergraduate education. Three percent of respondents indicated that they had a dermatology mentorship.

Perceptions of Dermatology—To further evaluate the level of interest that UiM premedical students have in the field of dermatology, students were asked how much they agree or disagree on whether the field of dermatology is interesting. Sixty-three percent of the students agreed that the field of dermatology is interesting, 34% remained uncertain, and 3% disagreed. Additionally, students were asked whether they would consider dermatology as a career; 54% of respondents would consider dermatology as a career, 30% remained uncertain, and 16% would not consider dermatology as a career choice.

Nearly all (95%) students agreed that dermatologists do valuable work that goes beyond the scope of cosmetic procedures such as neuromodulators, fillers, chemical peels, and lasers. Some students also noted they had personal experiences interacting with a dermatologist. For example, one student described visiting the dermatologist many times to get a treatment regimen for their eczema.

Overall themes from the survey are depicted in Table 2. Major themes found in the comments included the desire for more dermatology-related opportunities, mentorship, exposure, connections, and a discussion of disparities faced by Black patients and students within dermatology. Students also expressed an interest in dermatology and the desire to learn more about the specialty.

Comment

Interest in Dermatology—In this cross-sectional survey study of 152 UiM undergraduate students, it was found that many students were interested in dermatology as a career, and more than 70% would be interested in attending events that increased exposure to the field of dermatology. Of the students who had any exposure to dermatology, less than 5% had shadowed an actual dermatologist. The survey showed that there is great potential interest in exposing UiM undergraduate students to the field of dermatology. We found that UiM students are interested in learning more about dermatology, with 80% indicating that they would be willing to participate in dermatology-focused events if they were available. Overall, students mentioned a lack of opportunities, mentorship, exposure, and connections in dermatology despite their interest in the field.

Racial Disparities in Dermatology—Additionally, students discussed disparities they encountered with dermatology due to a lack of patient-provider race concordance and the perceived difference in care when encountering a race-concordant dermatologist. One student noted that they went to multiple White dermatologists for their eczema, and “it wasn’t until I was evaluated by a Black dermatologist (diagnosed with eczema as well) [that I was] prescribed . . . the perfect medication.” Another student noted how a Black dermatologist sparked their interest in getting to know more about the field and remarked that they “think it is an important field that lacks representation for Black people.” This research stresses the need for more dermatology mentorship among UiM undergraduates.

Family Influence on Career Selection—The majority of UiM students in our study became interested in medicine because of family, which is consistent with other studies. In a cross-sectional survey of 300 Pakistani students (150 medical and 150 nonmedical), 87% of students stated that their family had an influence on their career selection.⁸ In another study of 15 junior doctors in Sierra Leone, the most common reasons for pursuing medicine were the desire to help and familial and peer influence.⁹ This again showcases how family can have a positive impact on career selection for medical professionals and highlights the need for early intervention.

Shadowing—One way in which student exposure to dermatology can be effectively increased is by shadowing. In a study evaluating a 30-week shadowing program at the Pediatric Continuity Clinic in Los Angeles, California, a greater proportion of premedical students believed they had a good understanding of the job of a resident physician after the program’s completion compared to before starting the program (an increase from 78% to 100%).¹⁰ The proportion of students reporting a good understanding of the patient-physician relationship after completing the program also increased from 33% to 78%. Furthermore, 72% of the residents stated that having the undergraduates in the clinic was a positive experience.¹⁰ Thus, increasing shadowing opportunities is one extremely effective way to increase student knowledge and awareness of and exposure to dermatology.

Dermatology Mentors—Although 32% of students were interested in dermatology, 3% of students had mentorship in dermatology. In prior studies, it has been shown that mentorship is of great importance in student success and interest in pursuing a specialty. A report from the Association of American Medical Colleges 2019 Medical School Graduation Questionnaire found that the third most influential factor (52.1%) in specialty selection was role model influence.¹¹ In fact, having a role model is consistently one of the top 3 influences on student specialty choice and interest in the last 5 years of survey research. Some studies also have shown mentorship as a positive influence in specialty interest at the undergraduate and graduate levels. A study on an undergraduate student interest group noted that surgeon mentorship and exposure were positive factors to students’ interests in surgery.¹² In fact, the Association of American Medical Colleges noted that some surgical specialties, such as orthopedic surgery, had 45% of respondents who were interested in the specialty before medical school pursue their initial preference in medical school.¹³ Another survey corroborated these findings; more orthopedic-bound students compared with other specialties indicated they were more likely to pursue their field because of experiences prior to medical school.¹⁴

One of the reasons students might not have been exposed to as many opportunities for mentorship in dermatology is because the specialty is one of the smaller fields in medicine and tends to be concentrated in more well-resourced metropolitan areas.¹⁵ Dermatologists make up only 1.3% of the physician workforce.¹⁶ Because there might not be as much exposure to the field, students might also explore their interests in dermatology through other fields, such as through shadowing and observing primary care physicians who often treat patients with dermatologic issues. Skin diseases are a common reason for primary care visits, and one study suggested dermatologic diseases can make up approximately 8.4% of visits in primary care.¹⁷

Moreover, only 1% of medical schools require an elective in dermatology.¹⁸ With exposure being a crucial component to pursuing the specialty, it also is important to pursue formal mentorship within the specialty itself. One study noted that formal mentorship in dermatology was important for most (67%) respondents when considering the specialty; however, 39% of respondents mentioned receiving mentorship in the past. In fact, dermatology was one of the top 3 specialties for which respondents agreed that formal mentorship was important.¹⁹

Mentorship also has been shown to provide students with a variety of opportunities to develop personally and professionally. Some of these opportunities include increased confidence in their personal and professional success, increased desire to pursue a career in a field of interest, networking opportunities, career coaching, and support and research guidance.²⁰ A research study among medical students at Albert Einstein College of Medicine in New York, New York, found that US Medical Licensing Examination Step 1 scores, clinical grades, and the chance of not matching were important factors preventing them from applying to dermatology.²¹

Factors in Dermatology Residency Selection—A survey was conducted wherein 95 of 114 dermatology program directors expressed that among the top 5 criteria for dermatology resident selection were Step 1 scores and clinical grades, supporting the notion that academic factors were given a great emphasis during residency selection.²² Furthermore, among underrepresented minority medical students, a lack of diversity, the belief that minority students are seen negatively by residencies, socioeconomic factors, and not having mentors were major reasons for being dissuaded from applying to dermatology.²¹ These results showcase the heightened importance of mentors for underrepresented minority medical students in particular.

In graduate medical education, resources such as wikis, social networking sites, and blogs provide media through which trainees can communicate, exchange ideas, and enhance their medical knowledge.^23,24 A survey of 9606 osteopathic medical students showed that 35% of 992 respondents had used social media to learn more about residencies, and 10% believed that social media had influenced their choice of residency.²⁵ Given the impact social media has on recruitment, it also can be employed in a similar manner by dermatologists and dermatology residency programs to attract younger students to the field.

Access to More Opportunities to Learn About Dermatology—Besides shadowing and mentorship, other avenues of exposure to dermatology are possible and should be considered. In our study, 80% of students agreed that they would attend an event that increases exposure to dermatology if held by the premedical group, which suggests that students are eager to learn more about the field and want access to more opportunities, which could include learning procedures such as suturing or how to use a dermatoscope, attending guest speaker events, or participating in Learn2Derm volunteer events.

Learn2Derm was a skin cancer prevention fair first organized by medical students at George Washington University in Washington, DC. Students and residents sought to deliver sunscreens to underserved areas in Washington, DC, as well as teach residents about the importance of skin health. Participating in such events could be an excellent opportunity for all students to gain exposure to important topics in dermatology.²⁶

General Opinions of Dermatology—General opinions about dermatology and medicine were collected from the students through the optional “Additional Comments” section. Major themes found in the comments included the desire for more opportunities, mentorship, exposure, connections, and a discussion of disparities faced by Black patients/students within dermatology. Students also expressed an interest in dermatology and the desire to learn more about the specialty. From these themes, it can be gleaned that students are open to and eager for more opportunities to gain exposure and connections, and increasing the number of minority dermatologists is of importance.

Limitations—An important limitation of this study was the potential for selection bias, as the sample was chosen from a population at one university, which is not representative of the general population. Further, we only sampled students who were premedical and likely from a UiM racial group due to the demographics of the student population at the university, but given that the goal of the survey was to understand exposure to dermatology in underrepresented groups, we believe it was the appropriate population to target. Additionally, results were not compared with other more represented racial groups to see if these findings were unique to UiM undergraduate students.

Conclusion

Among premedical students, dermatology is an area of great interest with minimal opportunities available for exposure and learning because it is a smaller specialty with fewer experiences available for shadowing and mentorship. Although most UiM premedical students who were surveyed were exposed to the field through either the media or being a dermatology patient, fewer were exposed to the field through clinical experiences (such as shadowing) or mentorship. Most respondents found dermatology to be interesting and have considered pursuing it as a career. In particular, race-concordant mentoring in dermatologic care was valued by many students in garnering their interest in the field.

Most UiM students wanted more exposure to dermatology-related opportunities as well as mentorship and connections. Increasing shadowing, research, pipeline programs, and general events geared to dermatology are some modalities that could help improve exposure to dermatology for UiM students, especially for those interested in pursuing the field. This increased exposure can help positively influence more UiM students to pursue dermatology and help close the diversity gap in the field. Additionally, many were interested in attending potential dermatology informational events.

Given the fact that dermatology is a small field and mentorship may be hard to access, increasing informational events may be a more reasonable approach to inspiring and supporting interest. These events could include learning how to use certain tools and techniques, guest speaker events, or participating in educational volunteer efforts such as Learn2Derm.²⁶

Future research should focus on identifying beneficial factors of UiM premedical students who retain an interest in dermatology throughout their careers and actually apply to dermatology programs and become dermatologists. Those who do not apply to the specialty can be identified to understand potential dissuading factors and obstacles. Ultimately, more research and development of exposure opportunities, including mentorship programs and informational events, can be used to close the gap and improve diversity and health outcomes in dermatology.

Diversity of health care professionals improves medical outcomes and quality of life in patients. ¹ There is a lack of diversity in dermatology, with only 4.2% of dermatologists identifying as Hispanic and 3% identifying as African American, ² possibly due to a lack of early exposure to dermatology among high school and undergraduate students, a low number of underrepresented students in medical school, a lack of formal mentorship programs geared to underrepresented students, and implicit biases. ^1-4 Furthermore, the field is competitive, with many more applicants than available positions. In 2022, there were 851 applicants competing for 492 residency positions in dermatology. ⁵ Thus, it is important to educate young students about dermatology and understand root causes as to why the number of u nderrepresented in medicine (UiM) dermatologists remains stagnant.

According to Pritchett et al,⁴ it is crucial for dermatologists to interact with high school and college students to foster an early interest in dermatology. Many racial minority students do not progress from high school to college and then from college to medical school, which leaves a substantially reduced number of eligible UiM applicants who can progress into dermatology.⁶ Increasing the amount of UiM students going to medical school requires early mediation. Collaborating with pre-existing premedical school organizations through presentations and workshops is another way to promote an early interest in dermatology.⁴ Special consideration should be given to students who are UiM.

Among the general medical school curriculum, requirements for exposure to dermatology are not high. In one study, the median number of clinical and preclinical hours required was 10. Furthermore, 20% of 33 medical schools did not require preclinical dermatology hours (hours done before medical school rotations begin and in an academic setting), 36% required no clinical hours (rotational hours), 8% required no dermatology hours whatsoever, and only 10% required clinical dermatology rotation.³ Based on these findings, it is clear that dermatology is not well incorporated into medical school curricula. Furthermore, curricula have historically neglected to display adequate representation of skin of color.⁷ As a result, medical students generally have limited exposure to dermatology³ and are exposed even less to presentations of dermatologic issues in historically marginalized populations.⁷

Given the paucity of research on UiM students’ perceptions of dermatology prior to medical school, our cross-sectional survey study sought to evaluate the level of interest in dermatology of UiM premedical undergraduates. This survey specifically evaluated exposure to dermatology, preconceived notions about the field, and mentorship opportunities. By understanding these factors, dermatologists and dermatology residency programs can use this information to create mentorship opportunities and better adjust existing programs to meet students’ needs.

Methods

A 19-question multiple-choice survey was administered electronically (SurveyMonkey) in May 2020 to premedical students at Howard University (Washington, DC). One screening question was used: “What is your major?” Those who considered themselves a science major and/or with premedical interest were allowed to complete the survey. All students surveyed were members of the Health Professions Society at Howard University. Students who were interested in pursuing medical school were invited to respond. Approval for this study was obtained from the Howard University institutional review board (FWA00000891).

The survey was divided into 3 sections: Demographics, Exposure to Medicine and Dermatology, and Perceptions of Dermatology. The Demographics section addressed gender, age, and race/ethnicity. The Exposure to Medicine and Dermatology section addressed interest in attending medical school, shadowing experience, exposure to dermatology, and mentoring. The Perceptions of Dermatology section addressed preconceived notions about the field (eg, “dermatology is interesting and exciting”).

Statistical Analysis—The data represented are percentages based on the number of respondents who answered each question. Answers in response to “Please enter any comments” were organized into themes, and the number of respondents who discussed each theme was quantified into a table.

A total of 271 survey invitations were sent to premedical students at Howard University. Students were informed of the study protocol and asked to consent before proceeding to have their responses anonymously collected. Based on the screening question, 152 participants qualified for the survey, and 152 participants completed it (response rate, 56%; completion rate, 100%). Participants were asked to complete the survey only once.

Demographics—Eighty-four percent of respondents identified as science majors, and the remaining 16% identified as nonscience premedical. Ninety-four percent of participants identified as Black or African American; 3% as Asian or Asian American; and the remaining 3% as Other. Most respondents were female (82%), 16% were male, and 2% were either nonbinary or preferred not to answer. Ninety-nine percent were aged 18 to 24 years, and 1% were aged 25 to 34 years (Table 1).

Exposure to Medicine and Dermatology—Ninety-three percent of participants planned on attending medical school, and most students developed an interest in medicine from an early age. Ninety-six percent cited that they became interested in medicine prior to beginning their undergraduate education, and 4% developed an interest as freshmen or sophomores. When asked what led to their interest in medicine, family influence had the single greatest impact on students’ decision to pursue medicine (33%). Classes/school were the second most influential factor (24%), followed by volunteering (15%), shadowing (13%), other (7%), and peer influence (3%)(Figure 1).

Many (56%) premedical students surveyed had shadowing experience to varying degrees. Approximately 18% had fewer than 8 hours of shadowing experience, 24% had 8 to 40 hours, and 14% had more than 40 hours. However, many (43%) premedical students had no shadowing experience (Figure 2). Similarly, 30% of premedical students responded to having a physician as a mentor.

Regarding exposure to dermatology, 42% of premedical students had none. However, 58% of students had exposure to dermatology by being a patient themselves, 40% through seeing a dermatologist with a family member, 21% through seeing a dermatologist on television or social media, 5% through shadowing or volunteering, 3% through mentorship, and 1% through dermatology research (Figure 3).

Of students who said they were interested in dermatology (32%), 16% developed their interest before undergraduate education, while 9% developed interest in their freshman or sophomore year and 7% in their junior or senior year of undergraduate education. Three percent of respondents indicated that they had a dermatology mentorship.

Perceptions of Dermatology—To further evaluate the level of interest that UiM premedical students have in the field of dermatology, students were asked how much they agree or disagree on whether the field of dermatology is interesting. Sixty-three percent of the students agreed that the field of dermatology is interesting, 34% remained uncertain, and 3% disagreed. Additionally, students were asked whether they would consider dermatology as a career; 54% of respondents would consider dermatology as a career, 30% remained uncertain, and 16% would not consider dermatology as a career choice.

Nearly all (95%) students agreed that dermatologists do valuable work that goes beyond the scope of cosmetic procedures such as neuromodulators, fillers, chemical peels, and lasers. Some students also noted they had personal experiences interacting with a dermatologist. For example, one student described visiting the dermatologist many times to get a treatment regimen for their eczema.

Overall themes from the survey are depicted in Table 2. Major themes found in the comments included the desire for more dermatology-related opportunities, mentorship, exposure, connections, and a discussion of disparities faced by Black patients and students within dermatology. Students also expressed an interest in dermatology and the desire to learn more about the specialty.

Comment

Interest in Dermatology—In this cross-sectional survey study of 152 UiM undergraduate students, it was found that many students were interested in dermatology as a career, and more than 70% would be interested in attending events that increased exposure to the field of dermatology. Of the students who had any exposure to dermatology, less than 5% had shadowed an actual dermatologist. The survey showed that there is great potential interest in exposing UiM undergraduate students to the field of dermatology. We found that UiM students are interested in learning more about dermatology, with 80% indicating that they would be willing to participate in dermatology-focused events if they were available. Overall, students mentioned a lack of opportunities, mentorship, exposure, and connections in dermatology despite their interest in the field.

Racial Disparities in Dermatology—Additionally, students discussed disparities they encountered with dermatology due to a lack of patient-provider race concordance and the perceived difference in care when encountering a race-concordant dermatologist. One student noted that they went to multiple White dermatologists for their eczema, and “it wasn’t until I was evaluated by a Black dermatologist (diagnosed with eczema as well) [that I was] prescribed . . . the perfect medication.” Another student noted how a Black dermatologist sparked their interest in getting to know more about the field and remarked that they “think it is an important field that lacks representation for Black people.” This research stresses the need for more dermatology mentorship among UiM undergraduates.

Family Influence on Career Selection—The majority of UiM students in our study became interested in medicine because of family, which is consistent with other studies. In a cross-sectional survey of 300 Pakistani students (150 medical and 150 nonmedical), 87% of students stated that their family had an influence on their career selection.⁸ In another study of 15 junior doctors in Sierra Leone, the most common reasons for pursuing medicine were the desire to help and familial and peer influence.⁹ This again showcases how family can have a positive impact on career selection for medical professionals and highlights the need for early intervention.

Shadowing—One way in which student exposure to dermatology can be effectively increased is by shadowing. In a study evaluating a 30-week shadowing program at the Pediatric Continuity Clinic in Los Angeles, California, a greater proportion of premedical students believed they had a good understanding of the job of a resident physician after the program’s completion compared to before starting the program (an increase from 78% to 100%).¹⁰ The proportion of students reporting a good understanding of the patient-physician relationship after completing the program also increased from 33% to 78%. Furthermore, 72% of the residents stated that having the undergraduates in the clinic was a positive experience.¹⁰ Thus, increasing shadowing opportunities is one extremely effective way to increase student knowledge and awareness of and exposure to dermatology.

Dermatology Mentors—Although 32% of students were interested in dermatology, 3% of students had mentorship in dermatology. In prior studies, it has been shown that mentorship is of great importance in student success and interest in pursuing a specialty. A report from the Association of American Medical Colleges 2019 Medical School Graduation Questionnaire found that the third most influential factor (52.1%) in specialty selection was role model influence.¹¹ In fact, having a role model is consistently one of the top 3 influences on student specialty choice and interest in the last 5 years of survey research. Some studies also have shown mentorship as a positive influence in specialty interest at the undergraduate and graduate levels. A study on an undergraduate student interest group noted that surgeon mentorship and exposure were positive factors to students’ interests in surgery.¹² In fact, the Association of American Medical Colleges noted that some surgical specialties, such as orthopedic surgery, had 45% of respondents who were interested in the specialty before medical school pursue their initial preference in medical school.¹³ Another survey corroborated these findings; more orthopedic-bound students compared with other specialties indicated they were more likely to pursue their field because of experiences prior to medical school.¹⁴

One of the reasons students might not have been exposed to as many opportunities for mentorship in dermatology is because the specialty is one of the smaller fields in medicine and tends to be concentrated in more well-resourced metropolitan areas.¹⁵ Dermatologists make up only 1.3% of the physician workforce.¹⁶ Because there might not be as much exposure to the field, students might also explore their interests in dermatology through other fields, such as through shadowing and observing primary care physicians who often treat patients with dermatologic issues. Skin diseases are a common reason for primary care visits, and one study suggested dermatologic diseases can make up approximately 8.4% of visits in primary care.¹⁷

Moreover, only 1% of medical schools require an elective in dermatology.¹⁸ With exposure being a crucial component to pursuing the specialty, it also is important to pursue formal mentorship within the specialty itself. One study noted that formal mentorship in dermatology was important for most (67%) respondents when considering the specialty; however, 39% of respondents mentioned receiving mentorship in the past. In fact, dermatology was one of the top 3 specialties for which respondents agreed that formal mentorship was important.¹⁹

Mentorship also has been shown to provide students with a variety of opportunities to develop personally and professionally. Some of these opportunities include increased confidence in their personal and professional success, increased desire to pursue a career in a field of interest, networking opportunities, career coaching, and support and research guidance.²⁰ A research study among medical students at Albert Einstein College of Medicine in New York, New York, found that US Medical Licensing Examination Step 1 scores, clinical grades, and the chance of not matching were important factors preventing them from applying to dermatology.²¹

Factors in Dermatology Residency Selection—A survey was conducted wherein 95 of 114 dermatology program directors expressed that among the top 5 criteria for dermatology resident selection were Step 1 scores and clinical grades, supporting the notion that academic factors were given a great emphasis during residency selection.²² Furthermore, among underrepresented minority medical students, a lack of diversity, the belief that minority students are seen negatively by residencies, socioeconomic factors, and not having mentors were major reasons for being dissuaded from applying to dermatology.²¹ These results showcase the heightened importance of mentors for underrepresented minority medical students in particular.

In graduate medical education, resources such as wikis, social networking sites, and blogs provide media through which trainees can communicate, exchange ideas, and enhance their medical knowledge.^23,24 A survey of 9606 osteopathic medical students showed that 35% of 992 respondents had used social media to learn more about residencies, and 10% believed that social media had influenced their choice of residency.²⁵ Given the impact social media has on recruitment, it also can be employed in a similar manner by dermatologists and dermatology residency programs to attract younger students to the field.

Access to More Opportunities to Learn About Dermatology—Besides shadowing and mentorship, other avenues of exposure to dermatology are possible and should be considered. In our study, 80% of students agreed that they would attend an event that increases exposure to dermatology if held by the premedical group, which suggests that students are eager to learn more about the field and want access to more opportunities, which could include learning procedures such as suturing or how to use a dermatoscope, attending guest speaker events, or participating in Learn2Derm volunteer events.

Learn2Derm was a skin cancer prevention fair first organized by medical students at George Washington University in Washington, DC. Students and residents sought to deliver sunscreens to underserved areas in Washington, DC, as well as teach residents about the importance of skin health. Participating in such events could be an excellent opportunity for all students to gain exposure to important topics in dermatology.²⁶

General Opinions of Dermatology—General opinions about dermatology and medicine were collected from the students through the optional “Additional Comments” section. Major themes found in the comments included the desire for more opportunities, mentorship, exposure, connections, and a discussion of disparities faced by Black patients/students within dermatology. Students also expressed an interest in dermatology and the desire to learn more about the specialty. From these themes, it can be gleaned that students are open to and eager for more opportunities to gain exposure and connections, and increasing the number of minority dermatologists is of importance.

Limitations—An important limitation of this study was the potential for selection bias, as the sample was chosen from a population at one university, which is not representative of the general population. Further, we only sampled students who were premedical and likely from a UiM racial group due to the demographics of the student population at the university, but given that the goal of the survey was to understand exposure to dermatology in underrepresented groups, we believe it was the appropriate population to target. Additionally, results were not compared with other more represented racial groups to see if these findings were unique to UiM undergraduate students.

Conclusion

Among premedical students, dermatology is an area of great interest with minimal opportunities available for exposure and learning because it is a smaller specialty with fewer experiences available for shadowing and mentorship. Although most UiM premedical students who were surveyed were exposed to the field through either the media or being a dermatology patient, fewer were exposed to the field through clinical experiences (such as shadowing) or mentorship. Most respondents found dermatology to be interesting and have considered pursuing it as a career. In particular, race-concordant mentoring in dermatologic care was valued by many students in garnering their interest in the field.

Most UiM students wanted more exposure to dermatology-related opportunities as well as mentorship and connections. Increasing shadowing, research, pipeline programs, and general events geared to dermatology are some modalities that could help improve exposure to dermatology for UiM students, especially for those interested in pursuing the field. This increased exposure can help positively influence more UiM students to pursue dermatology and help close the diversity gap in the field. Additionally, many were interested in attending potential dermatology informational events.

Given the fact that dermatology is a small field and mentorship may be hard to access, increasing informational events may be a more reasonable approach to inspiring and supporting interest. These events could include learning how to use certain tools and techniques, guest speaker events, or participating in educational volunteer efforts such as Learn2Derm.²⁶

Future research should focus on identifying beneficial factors of UiM premedical students who retain an interest in dermatology throughout their careers and actually apply to dermatology programs and become dermatologists. Those who do not apply to the specialty can be identified to understand potential dissuading factors and obstacles. Ultimately, more research and development of exposure opportunities, including mentorship programs and informational events, can be used to close the gap and improve diversity and health outcomes in dermatology.

Diversity of health care professionals improves medical outcomes and quality of life in patients. ¹ There is a lack of diversity in dermatology, with only 4.2% of dermatologists identifying as Hispanic and 3% identifying as African American, ² possibly due to a lack of early exposure to dermatology among high school and undergraduate students, a low number of underrepresented students in medical school, a lack of formal mentorship programs geared to underrepresented students, and implicit biases. ^1-4 Furthermore, the field is competitive, with many more applicants than available positions. In 2022, there were 851 applicants competing for 492 residency positions in dermatology. ⁵ Thus, it is important to educate young students about dermatology and understand root causes as to why the number of u nderrepresented in medicine (UiM) dermatologists remains stagnant.

According to Pritchett et al,⁴ it is crucial for dermatologists to interact with high school and college students to foster an early interest in dermatology. Many racial minority students do not progress from high school to college and then from college to medical school, which leaves a substantially reduced number of eligible UiM applicants who can progress into dermatology.⁶ Increasing the amount of UiM students going to medical school requires early mediation. Collaborating with pre-existing premedical school organizations through presentations and workshops is another way to promote an early interest in dermatology.⁴ Special consideration should be given to students who are UiM.

Among the general medical school curriculum, requirements for exposure to dermatology are not high. In one study, the median number of clinical and preclinical hours required was 10. Furthermore, 20% of 33 medical schools did not require preclinical dermatology hours (hours done before medical school rotations begin and in an academic setting), 36% required no clinical hours (rotational hours), 8% required no dermatology hours whatsoever, and only 10% required clinical dermatology rotation.³ Based on these findings, it is clear that dermatology is not well incorporated into medical school curricula. Furthermore, curricula have historically neglected to display adequate representation of skin of color.⁷ As a result, medical students generally have limited exposure to dermatology³ and are exposed even less to presentations of dermatologic issues in historically marginalized populations.⁷

Given the paucity of research on UiM students’ perceptions of dermatology prior to medical school, our cross-sectional survey study sought to evaluate the level of interest in dermatology of UiM premedical undergraduates. This survey specifically evaluated exposure to dermatology, preconceived notions about the field, and mentorship opportunities. By understanding these factors, dermatologists and dermatology residency programs can use this information to create mentorship opportunities and better adjust existing programs to meet students’ needs.

Methods

A 19-question multiple-choice survey was administered electronically (SurveyMonkey) in May 2020 to premedical students at Howard University (Washington, DC). One screening question was used: “What is your major?” Those who considered themselves a science major and/or with premedical interest were allowed to complete the survey. All students surveyed were members of the Health Professions Society at Howard University. Students who were interested in pursuing medical school were invited to respond. Approval for this study was obtained from the Howard University institutional review board (FWA00000891).

The survey was divided into 3 sections: Demographics, Exposure to Medicine and Dermatology, and Perceptions of Dermatology. The Demographics section addressed gender, age, and race/ethnicity. The Exposure to Medicine and Dermatology section addressed interest in attending medical school, shadowing experience, exposure to dermatology, and mentoring. The Perceptions of Dermatology section addressed preconceived notions about the field (eg, “dermatology is interesting and exciting”).

Statistical Analysis—The data represented are percentages based on the number of respondents who answered each question. Answers in response to “Please enter any comments” were organized into themes, and the number of respondents who discussed each theme was quantified into a table.

A total of 271 survey invitations were sent to premedical students at Howard University. Students were informed of the study protocol and asked to consent before proceeding to have their responses anonymously collected. Based on the screening question, 152 participants qualified for the survey, and 152 participants completed it (response rate, 56%; completion rate, 100%). Participants were asked to complete the survey only once.

Demographics—Eighty-four percent of respondents identified as science majors, and the remaining 16% identified as nonscience premedical. Ninety-four percent of participants identified as Black or African American; 3% as Asian or Asian American; and the remaining 3% as Other. Most respondents were female (82%), 16% were male, and 2% were either nonbinary or preferred not to answer. Ninety-nine percent were aged 18 to 24 years, and 1% were aged 25 to 34 years (Table 1).

Exposure to Medicine and Dermatology—Ninety-three percent of participants planned on attending medical school, and most students developed an interest in medicine from an early age. Ninety-six percent cited that they became interested in medicine prior to beginning their undergraduate education, and 4% developed an interest as freshmen or sophomores. When asked what led to their interest in medicine, family influence had the single greatest impact on students’ decision to pursue medicine (33%). Classes/school were the second most influential factor (24%), followed by volunteering (15%), shadowing (13%), other (7%), and peer influence (3%)(Figure 1).

Many (56%) premedical students surveyed had shadowing experience to varying degrees. Approximately 18% had fewer than 8 hours of shadowing experience, 24% had 8 to 40 hours, and 14% had more than 40 hours. However, many (43%) premedical students had no shadowing experience (Figure 2). Similarly, 30% of premedical students responded to having a physician as a mentor.

Regarding exposure to dermatology, 42% of premedical students had none. However, 58% of students had exposure to dermatology by being a patient themselves, 40% through seeing a dermatologist with a family member, 21% through seeing a dermatologist on television or social media, 5% through shadowing or volunteering, 3% through mentorship, and 1% through dermatology research (Figure 3).

Of students who said they were interested in dermatology (32%), 16% developed their interest before undergraduate education, while 9% developed interest in their freshman or sophomore year and 7% in their junior or senior year of undergraduate education. Three percent of respondents indicated that they had a dermatology mentorship.

Perceptions of Dermatology—To further evaluate the level of interest that UiM premedical students have in the field of dermatology, students were asked how much they agree or disagree on whether the field of dermatology is interesting. Sixty-three percent of the students agreed that the field of dermatology is interesting, 34% remained uncertain, and 3% disagreed. Additionally, students were asked whether they would consider dermatology as a career; 54% of respondents would consider dermatology as a career, 30% remained uncertain, and 16% would not consider dermatology as a career choice.

Nearly all (95%) students agreed that dermatologists do valuable work that goes beyond the scope of cosmetic procedures such as neuromodulators, fillers, chemical peels, and lasers. Some students also noted they had personal experiences interacting with a dermatologist. For example, one student described visiting the dermatologist many times to get a treatment regimen for their eczema.

Overall themes from the survey are depicted in Table 2. Major themes found in the comments included the desire for more dermatology-related opportunities, mentorship, exposure, connections, and a discussion of disparities faced by Black patients and students within dermatology. Students also expressed an interest in dermatology and the desire to learn more about the specialty.

Comment

Interest in Dermatology—In this cross-sectional survey study of 152 UiM undergraduate students, it was found that many students were interested in dermatology as a career, and more than 70% would be interested in attending events that increased exposure to the field of dermatology. Of the students who had any exposure to dermatology, less than 5% had shadowed an actual dermatologist. The survey showed that there is great potential interest in exposing UiM undergraduate students to the field of dermatology. We found that UiM students are interested in learning more about dermatology, with 80% indicating that they would be willing to participate in dermatology-focused events if they were available. Overall, students mentioned a lack of opportunities, mentorship, exposure, and connections in dermatology despite their interest in the field.

Racial Disparities in Dermatology—Additionally, students discussed disparities they encountered with dermatology due to a lack of patient-provider race concordance and the perceived difference in care when encountering a race-concordant dermatologist. One student noted that they went to multiple White dermatologists for their eczema, and “it wasn’t until I was evaluated by a Black dermatologist (diagnosed with eczema as well) [that I was] prescribed . . . the perfect medication.” Another student noted how a Black dermatologist sparked their interest in getting to know more about the field and remarked that they “think it is an important field that lacks representation for Black people.” This research stresses the need for more dermatology mentorship among UiM undergraduates.

Family Influence on Career Selection—The majority of UiM students in our study became interested in medicine because of family, which is consistent with other studies. In a cross-sectional survey of 300 Pakistani students (150 medical and 150 nonmedical), 87% of students stated that their family had an influence on their career selection.⁸ In another study of 15 junior doctors in Sierra Leone, the most common reasons for pursuing medicine were the desire to help and familial and peer influence.⁹ This again showcases how family can have a positive impact on career selection for medical professionals and highlights the need for early intervention.

Shadowing—One way in which student exposure to dermatology can be effectively increased is by shadowing. In a study evaluating a 30-week shadowing program at the Pediatric Continuity Clinic in Los Angeles, California, a greater proportion of premedical students believed they had a good understanding of the job of a resident physician after the program’s completion compared to before starting the program (an increase from 78% to 100%).¹⁰ The proportion of students reporting a good understanding of the patient-physician relationship after completing the program also increased from 33% to 78%. Furthermore, 72% of the residents stated that having the undergraduates in the clinic was a positive experience.¹⁰ Thus, increasing shadowing opportunities is one extremely effective way to increase student knowledge and awareness of and exposure to dermatology.

Dermatology Mentors—Although 32% of students were interested in dermatology, 3% of students had mentorship in dermatology. In prior studies, it has been shown that mentorship is of great importance in student success and interest in pursuing a specialty. A report from the Association of American Medical Colleges 2019 Medical School Graduation Questionnaire found that the third most influential factor (52.1%) in specialty selection was role model influence.¹¹ In fact, having a role model is consistently one of the top 3 influences on student specialty choice and interest in the last 5 years of survey research. Some studies also have shown mentorship as a positive influence in specialty interest at the undergraduate and graduate levels. A study on an undergraduate student interest group noted that surgeon mentorship and exposure were positive factors to students’ interests in surgery.¹² In fact, the Association of American Medical Colleges noted that some surgical specialties, such as orthopedic surgery, had 45% of respondents who were interested in the specialty before medical school pursue their initial preference in medical school.¹³ Another survey corroborated these findings; more orthopedic-bound students compared with other specialties indicated they were more likely to pursue their field because of experiences prior to medical school.¹⁴

One of the reasons students might not have been exposed to as many opportunities for mentorship in dermatology is because the specialty is one of the smaller fields in medicine and tends to be concentrated in more well-resourced metropolitan areas.¹⁵ Dermatologists make up only 1.3% of the physician workforce.¹⁶ Because there might not be as much exposure to the field, students might also explore their interests in dermatology through other fields, such as through shadowing and observing primary care physicians who often treat patients with dermatologic issues. Skin diseases are a common reason for primary care visits, and one study suggested dermatologic diseases can make up approximately 8.4% of visits in primary care.¹⁷

Moreover, only 1% of medical schools require an elective in dermatology.¹⁸ With exposure being a crucial component to pursuing the specialty, it also is important to pursue formal mentorship within the specialty itself. One study noted that formal mentorship in dermatology was important for most (67%) respondents when considering the specialty; however, 39% of respondents mentioned receiving mentorship in the past. In fact, dermatology was one of the top 3 specialties for which respondents agreed that formal mentorship was important.¹⁹

Mentorship also has been shown to provide students with a variety of opportunities to develop personally and professionally. Some of these opportunities include increased confidence in their personal and professional success, increased desire to pursue a career in a field of interest, networking opportunities, career coaching, and support and research guidance.²⁰ A research study among medical students at Albert Einstein College of Medicine in New York, New York, found that US Medical Licensing Examination Step 1 scores, clinical grades, and the chance of not matching were important factors preventing them from applying to dermatology.²¹

Factors in Dermatology Residency Selection—A survey was conducted wherein 95 of 114 dermatology program directors expressed that among the top 5 criteria for dermatology resident selection were Step 1 scores and clinical grades, supporting the notion that academic factors were given a great emphasis during residency selection.²² Furthermore, among underrepresented minority medical students, a lack of diversity, the belief that minority students are seen negatively by residencies, socioeconomic factors, and not having mentors were major reasons for being dissuaded from applying to dermatology.²¹ These results showcase the heightened importance of mentors for underrepresented minority medical students in particular.

In graduate medical education, resources such as wikis, social networking sites, and blogs provide media through which trainees can communicate, exchange ideas, and enhance their medical knowledge.^23,24 A survey of 9606 osteopathic medical students showed that 35% of 992 respondents had used social media to learn more about residencies, and 10% believed that social media had influenced their choice of residency.²⁵ Given the impact social media has on recruitment, it also can be employed in a similar manner by dermatologists and dermatology residency programs to attract younger students to the field.

Access to More Opportunities to Learn About Dermatology—Besides shadowing and mentorship, other avenues of exposure to dermatology are possible and should be considered. In our study, 80% of students agreed that they would attend an event that increases exposure to dermatology if held by the premedical group, which suggests that students are eager to learn more about the field and want access to more opportunities, which could include learning procedures such as suturing or how to use a dermatoscope, attending guest speaker events, or participating in Learn2Derm volunteer events.

Learn2Derm was a skin cancer prevention fair first organized by medical students at George Washington University in Washington, DC. Students and residents sought to deliver sunscreens to underserved areas in Washington, DC, as well as teach residents about the importance of skin health. Participating in such events could be an excellent opportunity for all students to gain exposure to important topics in dermatology.²⁶

General Opinions of Dermatology—General opinions about dermatology and medicine were collected from the students through the optional “Additional Comments” section. Major themes found in the comments included the desire for more opportunities, mentorship, exposure, connections, and a discussion of disparities faced by Black patients/students within dermatology. Students also expressed an interest in dermatology and the desire to learn more about the specialty. From these themes, it can be gleaned that students are open to and eager for more opportunities to gain exposure and connections, and increasing the number of minority dermatologists is of importance.

Limitations—An important limitation of this study was the potential for selection bias, as the sample was chosen from a population at one university, which is not representative of the general population. Further, we only sampled students who were premedical and likely from a UiM racial group due to the demographics of the student population at the university, but given that the goal of the survey was to understand exposure to dermatology in underrepresented groups, we believe it was the appropriate population to target. Additionally, results were not compared with other more represented racial groups to see if these findings were unique to UiM undergraduate students.

Conclusion

Among premedical students, dermatology is an area of great interest with minimal opportunities available for exposure and learning because it is a smaller specialty with fewer experiences available for shadowing and mentorship. Although most UiM premedical students who were surveyed were exposed to the field through either the media or being a dermatology patient, fewer were exposed to the field through clinical experiences (such as shadowing) or mentorship. Most respondents found dermatology to be interesting and have considered pursuing it as a career. In particular, race-concordant mentoring in dermatologic care was valued by many students in garnering their interest in the field.

Most UiM students wanted more exposure to dermatology-related opportunities as well as mentorship and connections. Increasing shadowing, research, pipeline programs, and general events geared to dermatology are some modalities that could help improve exposure to dermatology for UiM students, especially for those interested in pursuing the field. This increased exposure can help positively influence more UiM students to pursue dermatology and help close the diversity gap in the field. Additionally, many were interested in attending potential dermatology informational events.

Given the fact that dermatology is a small field and mentorship may be hard to access, increasing informational events may be a more reasonable approach to inspiring and supporting interest. These events could include learning how to use certain tools and techniques, guest speaker events, or participating in educational volunteer efforts such as Learn2Derm.²⁶

Future research should focus on identifying beneficial factors of UiM premedical students who retain an interest in dermatology throughout their careers and actually apply to dermatology programs and become dermatologists. Those who do not apply to the specialty can be identified to understand potential dissuading factors and obstacles. Ultimately, more research and development of exposure opportunities, including mentorship programs and informational events, can be used to close the gap and improve diversity and health outcomes in dermatology.