Cutis

When I was a medical student rotating in dermatology, a patient with extensive alopecia looked at my long thick hair and said tearfully, “I just wish I could have hair like yours.”

I smiled, removed my wig, and replied, “You can have hair like mine.”

Determination and Perseverance

I was 2 years old when I was given a diagnosis of alopecia areata. Bald spots on my scalp would come and go for years but were not overly burdensome until I turned 12. At that point, my hair loss escalated despite frequent intralesional injections of triamcinolone; every 2 steps forward were followed by 3 steps backward.

As a freshman in high school, I finally took control of my condition and emotions, shaved my head, and purchased a wig—actions that confronted my hair loss and awoke a determination and perseverance that I did not think I would ever gain while living with this condition. As McGettigan¹ wrote in the Journal of the American Academy of Dermatology in 2004, “Being diagnosed with [alopecia areata] does not mean one cannot have a full and meaningful life. By choosing to confront the condition and turn its negative aspects into positive actions, one can succeed in life.”¹

As a Provider, Another Perspective

Now, as a dermatology resident, I have the distinct perspective of being patient and provider. Patients often want to know, “Why is this happening?”, “Is my hair going to grow back?”, and “What treatments are available?”

They want to feel supported, understood, and heard.

As health care providers, we must understand that hair loss can result in overwhelming fear, hopelessness, and loss of self-esteem. Although we can give good news and offer helpful treatment options to some patients, there are those for whom medical treatment fails, and we can offer no more than a supportive hand and warm smile.

But can we do even more than that? The answer is: “Yes.”

Management Options

I recommend that all patients with hair loss should receive a copy of the aforementioned McGettigan¹ article, “Ahead With No Hair,” which is geared toward patients with alopecia areata but offers inspiring words to any patient struggling to cope with hair loss. Dermatologists also can offer management options for patients with hair loss, including camouflage, wigs, and cosmetic replacement of eyelashes and eyebrows. Of note, several companies offer wigs and brow replacement options for men and children.

Camouflage
We can offer creative and readily available camouflage options for patients with hair loss. For small bald spots and thinning hair on the scalp, keratin hair-building fibers can be extremely useful. This over-the-counter product comes in a variety of natural hair colors, conceals the underlying skin, and adds fullness to hair. The keratin fibers have an innate static charge that allows them to adhere to the hair shaft. Daily application typically is necessary; duration can be maximized if hair spray or other brand-specific bonding spray is used following application of the fibers. A simple online search using the term keratin hair building fibers will reveal many online and in-store options with 4- or 5-star reviews. Most negative reviews pertain to sweating or moisture that causes clumping, but overall this is an easy and affordable option for mild hair loss.

Wigs
For patients hoping to mask moderate or severe hair loss, I recommend wigs, which can be made from synthetic fibers or human hair. In order to effectively guide patients, it is helpful for providers to have some knowledge about the 2 types of wigs. Synthetic wigs are of variable quality, ranging from costume-grade to top-quality products that look and feel like human hair. They are more affordable and often are easier to maintain than human-hair wigs, and hairstyles hold up better after washing. Many synthetic wigs cannot withstand heat from a hot iron and have a slightly shorter lifespan (6–12 months) than human-hair wigs (1–2 years).

Human hair wigs are made of real human hair, so they look and feel natural. These wigs can be made from European, African, Indian, Malaysian, Chinese, or other ethnic hair. Patients can choose the texture of the hair, including silky (smooth), kinky (mimicking natural blow-dried Black hair), and yaki (mimicking relaxed Black hair), as well as the curl pattern (straight, wavy, or curly), length, color, density, and cap construction.

The cap of a wig is what the hair is tied to. The construction of wig caps varies to allow for realistic hair lines as well as security for active use or up-dos. Among the many cap-construction options, the most realistic-appearing are hand-tied monofilament, lace-front, and full-lace wigs, all of which may require tape or glue to keep them in place. Some wig companies offer nonslip so-called “alopecia caps” for patients with no scalp hair. Patients who find their wig irritating to the scalp should consider wearing a nylon wig cap or liner.

Wigs can be purchased in store or online and can be pre-made or custom-built to be tailored to the patient’s specific desires and expectations. The cost depends on the type and quality of hair, cap construction, and length; prices can range from less than $100 to more than $5000.

When choosing a wig, which option—synthetic or human hair—is better for a given patient? Synthetic wigs are rather inexpensive and easy to care for, making them great for new users and those who want to try different styles and colors. Human-hair wigs can be custom-made to match the patient’s natural hair; however, they require extra care to maintain their longevity. Both types of wigs have pros and cons depending on the patient’s budget, time required for maintenance and styling, and needs (Table 1). I encourage patients to have fun with all wig options: Now is the time, I tell them, to try out the cute or daring hair style they have always wanted. The great thing is that if the patient does not like their wig, they can readily change it.

Resources Abound

Experiencing and treating hair loss can be overwhelming, but there are countless resources available for patients. The NAAF has utility beyond the concerns of alopecia areata patients; there also is useful information on YouTube and social media, and support groups exist for hair-loss patients. I recommend starting with the NAAF website, which offers many helpful resources and support groups for patients and their families, including tips on applying for insurance reimbursement and drafting an appeal letter. Lastly, several nonprofit organizations serve the hair-replacement needs of children and adults with hair loss (Table 4).

Final Thoughts

My experience as a patient with alopecia has been long and initially was challenging; however, I found the silver lining after choosing to confront my literal and figurative “losses” and move forward—to grow, so to speak. With the use of custom-made human-hair wigs, false strip eyelashes, and a mix of eyebrow replacement options, I have been able to regain my confidence and self-esteem. Now, my goal as a physician—a goal that I hope you will share—is to be knowledgeable about hair-replacement options and provide information and resources to patients to help them feel empowered, brave, and beautiful.

When I was a medical student rotating in dermatology, a patient with extensive alopecia looked at my long thick hair and said tearfully, “I just wish I could have hair like yours.”

I smiled, removed my wig, and replied, “You can have hair like mine.”

Determination and Perseverance

I was 2 years old when I was given a diagnosis of alopecia areata. Bald spots on my scalp would come and go for years but were not overly burdensome until I turned 12. At that point, my hair loss escalated despite frequent intralesional injections of triamcinolone; every 2 steps forward were followed by 3 steps backward.

As a freshman in high school, I finally took control of my condition and emotions, shaved my head, and purchased a wig—actions that confronted my hair loss and awoke a determination and perseverance that I did not think I would ever gain while living with this condition. As McGettigan¹ wrote in the Journal of the American Academy of Dermatology in 2004, “Being diagnosed with [alopecia areata] does not mean one cannot have a full and meaningful life. By choosing to confront the condition and turn its negative aspects into positive actions, one can succeed in life.”¹

As a Provider, Another Perspective

Now, as a dermatology resident, I have the distinct perspective of being patient and provider. Patients often want to know, “Why is this happening?”, “Is my hair going to grow back?”, and “What treatments are available?”

They want to feel supported, understood, and heard.

As health care providers, we must understand that hair loss can result in overwhelming fear, hopelessness, and loss of self-esteem. Although we can give good news and offer helpful treatment options to some patients, there are those for whom medical treatment fails, and we can offer no more than a supportive hand and warm smile.

But can we do even more than that? The answer is: “Yes.”

Management Options

I recommend that all patients with hair loss should receive a copy of the aforementioned McGettigan¹ article, “Ahead With No Hair,” which is geared toward patients with alopecia areata but offers inspiring words to any patient struggling to cope with hair loss. Dermatologists also can offer management options for patients with hair loss, including camouflage, wigs, and cosmetic replacement of eyelashes and eyebrows. Of note, several companies offer wigs and brow replacement options for men and children.

Camouflage
We can offer creative and readily available camouflage options for patients with hair loss. For small bald spots and thinning hair on the scalp, keratin hair-building fibers can be extremely useful. This over-the-counter product comes in a variety of natural hair colors, conceals the underlying skin, and adds fullness to hair. The keratin fibers have an innate static charge that allows them to adhere to the hair shaft. Daily application typically is necessary; duration can be maximized if hair spray or other brand-specific bonding spray is used following application of the fibers. A simple online search using the term keratin hair building fibers will reveal many online and in-store options with 4- or 5-star reviews. Most negative reviews pertain to sweating or moisture that causes clumping, but overall this is an easy and affordable option for mild hair loss.

Wigs
For patients hoping to mask moderate or severe hair loss, I recommend wigs, which can be made from synthetic fibers or human hair. In order to effectively guide patients, it is helpful for providers to have some knowledge about the 2 types of wigs. Synthetic wigs are of variable quality, ranging from costume-grade to top-quality products that look and feel like human hair. They are more affordable and often are easier to maintain than human-hair wigs, and hairstyles hold up better after washing. Many synthetic wigs cannot withstand heat from a hot iron and have a slightly shorter lifespan (6–12 months) than human-hair wigs (1–2 years).

Human hair wigs are made of real human hair, so they look and feel natural. These wigs can be made from European, African, Indian, Malaysian, Chinese, or other ethnic hair. Patients can choose the texture of the hair, including silky (smooth), kinky (mimicking natural blow-dried Black hair), and yaki (mimicking relaxed Black hair), as well as the curl pattern (straight, wavy, or curly), length, color, density, and cap construction.

The cap of a wig is what the hair is tied to. The construction of wig caps varies to allow for realistic hair lines as well as security for active use or up-dos. Among the many cap-construction options, the most realistic-appearing are hand-tied monofilament, lace-front, and full-lace wigs, all of which may require tape or glue to keep them in place. Some wig companies offer nonslip so-called “alopecia caps” for patients with no scalp hair. Patients who find their wig irritating to the scalp should consider wearing a nylon wig cap or liner.

Wigs can be purchased in store or online and can be pre-made or custom-built to be tailored to the patient’s specific desires and expectations. The cost depends on the type and quality of hair, cap construction, and length; prices can range from less than $100 to more than $5000.

When choosing a wig, which option—synthetic or human hair—is better for a given patient? Synthetic wigs are rather inexpensive and easy to care for, making them great for new users and those who want to try different styles and colors. Human-hair wigs can be custom-made to match the patient’s natural hair; however, they require extra care to maintain their longevity. Both types of wigs have pros and cons depending on the patient’s budget, time required for maintenance and styling, and needs (Table 1). I encourage patients to have fun with all wig options: Now is the time, I tell them, to try out the cute or daring hair style they have always wanted. The great thing is that if the patient does not like their wig, they can readily change it.

Resources Abound

Experiencing and treating hair loss can be overwhelming, but there are countless resources available for patients. The NAAF has utility beyond the concerns of alopecia areata patients; there also is useful information on YouTube and social media, and support groups exist for hair-loss patients. I recommend starting with the NAAF website, which offers many helpful resources and support groups for patients and their families, including tips on applying for insurance reimbursement and drafting an appeal letter. Lastly, several nonprofit organizations serve the hair-replacement needs of children and adults with hair loss (Table 4).

Final Thoughts

My experience as a patient with alopecia has been long and initially was challenging; however, I found the silver lining after choosing to confront my literal and figurative “losses” and move forward—to grow, so to speak. With the use of custom-made human-hair wigs, false strip eyelashes, and a mix of eyebrow replacement options, I have been able to regain my confidence and self-esteem. Now, my goal as a physician—a goal that I hope you will share—is to be knowledgeable about hair-replacement options and provide information and resources to patients to help them feel empowered, brave, and beautiful.

When I was a medical student rotating in dermatology, a patient with extensive alopecia looked at my long thick hair and said tearfully, “I just wish I could have hair like yours.”

I smiled, removed my wig, and replied, “You can have hair like mine.”

Determination and Perseverance

I was 2 years old when I was given a diagnosis of alopecia areata. Bald spots on my scalp would come and go for years but were not overly burdensome until I turned 12. At that point, my hair loss escalated despite frequent intralesional injections of triamcinolone; every 2 steps forward were followed by 3 steps backward.

As a freshman in high school, I finally took control of my condition and emotions, shaved my head, and purchased a wig—actions that confronted my hair loss and awoke a determination and perseverance that I did not think I would ever gain while living with this condition. As McGettigan¹ wrote in the Journal of the American Academy of Dermatology in 2004, “Being diagnosed with [alopecia areata] does not mean one cannot have a full and meaningful life. By choosing to confront the condition and turn its negative aspects into positive actions, one can succeed in life.”¹

As a Provider, Another Perspective

Now, as a dermatology resident, I have the distinct perspective of being patient and provider. Patients often want to know, “Why is this happening?”, “Is my hair going to grow back?”, and “What treatments are available?”

They want to feel supported, understood, and heard.

As health care providers, we must understand that hair loss can result in overwhelming fear, hopelessness, and loss of self-esteem. Although we can give good news and offer helpful treatment options to some patients, there are those for whom medical treatment fails, and we can offer no more than a supportive hand and warm smile.

But can we do even more than that? The answer is: “Yes.”

Management Options

I recommend that all patients with hair loss should receive a copy of the aforementioned McGettigan¹ article, “Ahead With No Hair,” which is geared toward patients with alopecia areata but offers inspiring words to any patient struggling to cope with hair loss. Dermatologists also can offer management options for patients with hair loss, including camouflage, wigs, and cosmetic replacement of eyelashes and eyebrows. Of note, several companies offer wigs and brow replacement options for men and children.

Camouflage
We can offer creative and readily available camouflage options for patients with hair loss. For small bald spots and thinning hair on the scalp, keratin hair-building fibers can be extremely useful. This over-the-counter product comes in a variety of natural hair colors, conceals the underlying skin, and adds fullness to hair. The keratin fibers have an innate static charge that allows them to adhere to the hair shaft. Daily application typically is necessary; duration can be maximized if hair spray or other brand-specific bonding spray is used following application of the fibers. A simple online search using the term keratin hair building fibers will reveal many online and in-store options with 4- or 5-star reviews. Most negative reviews pertain to sweating or moisture that causes clumping, but overall this is an easy and affordable option for mild hair loss.

Wigs
For patients hoping to mask moderate or severe hair loss, I recommend wigs, which can be made from synthetic fibers or human hair. In order to effectively guide patients, it is helpful for providers to have some knowledge about the 2 types of wigs. Synthetic wigs are of variable quality, ranging from costume-grade to top-quality products that look and feel like human hair. They are more affordable and often are easier to maintain than human-hair wigs, and hairstyles hold up better after washing. Many synthetic wigs cannot withstand heat from a hot iron and have a slightly shorter lifespan (6–12 months) than human-hair wigs (1–2 years).

Human hair wigs are made of real human hair, so they look and feel natural. These wigs can be made from European, African, Indian, Malaysian, Chinese, or other ethnic hair. Patients can choose the texture of the hair, including silky (smooth), kinky (mimicking natural blow-dried Black hair), and yaki (mimicking relaxed Black hair), as well as the curl pattern (straight, wavy, or curly), length, color, density, and cap construction.

The cap of a wig is what the hair is tied to. The construction of wig caps varies to allow for realistic hair lines as well as security for active use or up-dos. Among the many cap-construction options, the most realistic-appearing are hand-tied monofilament, lace-front, and full-lace wigs, all of which may require tape or glue to keep them in place. Some wig companies offer nonslip so-called “alopecia caps” for patients with no scalp hair. Patients who find their wig irritating to the scalp should consider wearing a nylon wig cap or liner.

Wigs can be purchased in store or online and can be pre-made or custom-built to be tailored to the patient’s specific desires and expectations. The cost depends on the type and quality of hair, cap construction, and length; prices can range from less than $100 to more than $5000.

When choosing a wig, which option—synthetic or human hair—is better for a given patient? Synthetic wigs are rather inexpensive and easy to care for, making them great for new users and those who want to try different styles and colors. Human-hair wigs can be custom-made to match the patient’s natural hair; however, they require extra care to maintain their longevity. Both types of wigs have pros and cons depending on the patient’s budget, time required for maintenance and styling, and needs (Table 1). I encourage patients to have fun with all wig options: Now is the time, I tell them, to try out the cute or daring hair style they have always wanted. The great thing is that if the patient does not like their wig, they can readily change it.

Resources Abound

Experiencing and treating hair loss can be overwhelming, but there are countless resources available for patients. The NAAF has utility beyond the concerns of alopecia areata patients; there also is useful information on YouTube and social media, and support groups exist for hair-loss patients. I recommend starting with the NAAF website, which offers many helpful resources and support groups for patients and their families, including tips on applying for insurance reimbursement and drafting an appeal letter. Lastly, several nonprofit organizations serve the hair-replacement needs of children and adults with hair loss (Table 4).

Final Thoughts

My experience as a patient with alopecia has been long and initially was challenging; however, I found the silver lining after choosing to confront my literal and figurative “losses” and move forward—to grow, so to speak. With the use of custom-made human-hair wigs, false strip eyelashes, and a mix of eyebrow replacement options, I have been able to regain my confidence and self-esteem. Now, my goal as a physician—a goal that I hope you will share—is to be knowledgeable about hair-replacement options and provide information and resources to patients to help them feel empowered, brave, and beautiful.

To the Editor:

Psoriasis vulgaris is a chronic autoimmune inflammatory disease and biologic agents, such as anti–tumor necrosis factor α (TNF-α), are alternative drugs in case of resistance or adverse events to conventional ones.¹ The limitation of these agents is immunosuppression that may cause infections such as tuberculosis (TB). Prophylaxis is indicated to latent TB diseases if the purified protein derivative (tuberculin) skin test is higher than 5 mm before starting these treatments. The challenge in TB treatment is adverse drug reactions (ADRs) that are reported in 4% to 6% of cases.^2,3

Erythema multiforme–like dermatitis is a rare skin rash that develops due to isoniazid (INH). The clinical presentation includes erythematoedematous lesions in an acral distribution with no mucosal involvement and systemic exposure to INH. Skin biopsy and patch tests are the supportive diagnostic methods. Isoniazid-associated skin rashes rarely are reported and generally are not severe enough to terminate the drug. We present a patient with psoriasis who received TB prophylaxis before anti–TNF-α use. He presented with erythema multiforme–like dermatitis due to INH. Withdrawal of the drug and treatment of the lesions were the first steps of intolerance, followed by a patch test with the culprit drug after recovery. We discuss the diagnostic drug allergy evaluation and treatment approach.

A 37-year-old man presented with a 15-year history of severe psoriasis with frequent flares. He was treated with various topical and systemic agents including acitretin and methotrexate at 4-year intervals. Despite the addition of phototherapy, he underwent a new treatment with anti–TNF-α, as the disease control with other treatments was insufficient. Before starting anti–TNF-α, preventive treatment against TB with INH (300 mg/d) was indicated with 20 mm of purified protein derivative. On approximately the 20th day of treatment, he developed pruritic erythema with desquamation and exfoliation localized to the hands and feet (Figure 1). Isoniazid was discontinued and a topical steroid was initiated. After 3 weeks, the skin lesions were completely improved and INH was reinitiated at the same dose with antihistamine prophylaxis (oral levocetirizine 5 mg/d). Seven days later, similar skin lesions presented that were more extensive on the arms and legs (Figure 2). Complete blood cell counts, renal and hepatic function tests, and hepatitis markers were within reference range in consultation with the allergy division. To distinguish the lesions from a psoriasis attack, a punch biopsy of the eruptive dermatitis showed erythema multiforme–like dermatitis including dermal edema and perivascular lymphocytic infiltration with no relation to psoriasis but consistent with a drug eruption. Isoniazid was discontinued, and the skin lesions resolved after 4 weeks of topical steroid and oral antihistamine use (Figure 3). There was no other drug use except INH, and a skin patch test with INH was positive at 72 hours (Figure 4). Skin tests with INH were done to 5 healthy lesions that were negative. Finally, TB prophylaxis was performed with rifampicin (10 mg/kg/d [600 mg/d]) for 4 months with no ADRs. The patient’s psoriasis lesions improved with anti–TNF-α that was initiated 1 month after starting TB prevention with rifampicin.

This case of erythema multiforme–like dermatitis was diagnosed with acral involvement, a positive patch test to INH, and lymphocytic inflammation in a skin biopsy. It was a drug-induced reaction, as skin lesions developed during INH intake and improved after drug withdrawal.

Isoniazid, also known as isonicotinylhydrazide, is an oral antibiotic used for the treatment of TB and other mycobacteria. Protective treatment against latent TB primarily is done with daily INH for 6 or 9 months; alternatively, INH may be taken weekly with rifapentine for 3 months or daily with rifampicin for 4 months. Daily rifampicin alone for 4 months also is an option. In general, these regimens have similar efficacy; however, in terms of safety, the rifampicin and rifapentine combination regimens have fewer hepatotoxicity events compared to the INH alone regimen, but there are more cutaneous and flulike reactions and gastrointestinal intolerance.⁴ Cutaneous ADRs to TB treatment such as mild itchiness and cutaneous eruptions usually are observed within 2 months of drug initiation. Pyrazinamide was reported as the most common drug associated with cutaneous ADRs, and INH was the rarest offending drug.⁵

The frequency of ADRs to INH is approximately 5.4%, and the most prevalent ADRs include asymptomatic elevation of serum liver enzyme concentrations, peripheral neuropathy, and hepatotoxicity, and skin lesions are less common.² Our patient’s laboratory test results excluded vitamin B deficiency, hepatic and renal dysfunction, and neuropathy.

Previously reported skin reactions related to INH were late-type reactions such as maculopapular rash, dermatitis, erythema multiforme, drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, Stevens-Johnson syndrome, and toxic epidermal necrolysis.^5,6 The concerning prediagnosis of psoriatic exacerbation in our patient was ruled out by the absence of typical skin lesions such as well-defined, erythematous plaques and pustules and atypical localization such as the dorsal hands and feet rather than the knees, elbows, lumbosacral region, scalp, and abdomen, which is typical of psoriasis. DRESS syndrome was unlikely with the absence of fever, lymphadenopathy, hypereosinophilia, leukocytosis, and renal and hepatic dysfunction.⁷ There were no widespread blisters, epidermal detachment, or mucosal involvement on the trunk or face typically associated with Stevens-Johnson syndrome and toxic epidermal necrolysis.^7,8 A possible diagnosis of contact dermatitis was suspected with likely skin lesions as exfoliation and chapping, typical localization on the hands and feet, and positive patch test that supported sensitization to the drug. However, the patient’s skin lesions were not eczematous (characterized by erythema, vesiculation, exudation, or bullous edema in the acute phase), and were not localized to areas of irritant exposure.³ In our patient, erythematoedematous lesions in an acral distribution with no mucosal involvement and systemic exposure to INH was compatible with erythema multiforme, whereas the absence of target appearance, positive patch test, and late appearance were incompatible with erythema multiforme.⁸

Because the clinical picture did not fit contact dermatitis or erythema multiforme, a diagnosis of erythema multiforme–like noneczematous dermatitis was suggested. Noneczematous dermatitis has subtypes that include purpuric, lichenoid, pustular, lymphomatoid, dyshidrosiform, and pigmented, as well as erythema multiforme–like contact eruptions.⁹ These clinical entities are not associated with contact exposure, but are related to systemic exposure, as seen in our patient.¹⁰ The patch test positivity and skin biopsy report also supported the diagnosis of erythema multiforme–like dermatitis. Erythema multiforme–like dermatitis is thought to be caused by medications or infections inducing immunocomplexes and lymphocytic infiltration in the dermis and subepidermis. Nevertheless, the prognosis was self-limiting in both.⁸ The clinical polymorphism caused by INH in this patient was suggested to be related with individual susceptibility, variability of contact-activating modalities, and the targeted cutaneous structures. Furthermore, among the risk factors for cutaneous ADRs—HIV, polypharmacy, older age, and preexisting renal and liver impairment—the only notable factor in this patient was psoriasis as an autoimmune disorder.

Patients with skin diseases such as psoriasis should be followed up by closer monitoring during INH use. Withdrawal of the drug and symptomatic treatment of the lesions with corticosteroid and antihistamine are the first steps of drug intolerance. After complete recovery and termination of antiallergic drugs, diagnostic tests are recommended if the drug reaction was not life-threatening. Skin prick and intradermal tests are useful in early-type drug reactions, whereas patch testing and late evaluation of an intradermal test may be helpful in the diagnosis of delayed-type reactions. The full dose of INH is avoided in an intradermal test against irritation. A patch test with INH was performed by diluting a 100-mg tablet with 1 mL of distilled water, and used as 1/100, 1/10, and 1/1 dilutions.⁸ Patch testing with INH also was done in 5 healthy control patients to exclude the irritation effect in this case. The rechallenge of INH was done in a controlled manner in our patient to rule out psoriasis activation since it was a localized skin reaction with no serious ADR. An oral provocation test with the culprit drug is the gold standard of drug allergy diagnosis that should be done in a tertiary hospital with an intensive care unit.

This case of erythema multiforme–like dermatitis due to INH is interesting due to systemic intake of INH, which resulted in dermatitis with localized involvement similar to erythema multiforme but with no immunologic processes or prior sensitization. With the increasing use of anti–TNF-α treatment, INH use will be more prevalent than in the past for the treatment of latent TB. Even though the skin-restricted ADRs of INH are rare and minor, particular attention should be paid to patients with dermatologic diseases. In our case, diagnostic drug allergy evaluation was performed to optimize the second-line treatment of TB infection, in addition to early withdrawal of the culprit drug.

To the Editor:

Psoriasis vulgaris is a chronic autoimmune inflammatory disease and biologic agents, such as anti–tumor necrosis factor α (TNF-α), are alternative drugs in case of resistance or adverse events to conventional ones.¹ The limitation of these agents is immunosuppression that may cause infections such as tuberculosis (TB). Prophylaxis is indicated to latent TB diseases if the purified protein derivative (tuberculin) skin test is higher than 5 mm before starting these treatments. The challenge in TB treatment is adverse drug reactions (ADRs) that are reported in 4% to 6% of cases.^2,3

Erythema multiforme–like dermatitis is a rare skin rash that develops due to isoniazid (INH). The clinical presentation includes erythematoedematous lesions in an acral distribution with no mucosal involvement and systemic exposure to INH. Skin biopsy and patch tests are the supportive diagnostic methods. Isoniazid-associated skin rashes rarely are reported and generally are not severe enough to terminate the drug. We present a patient with psoriasis who received TB prophylaxis before anti–TNF-α use. He presented with erythema multiforme–like dermatitis due to INH. Withdrawal of the drug and treatment of the lesions were the first steps of intolerance, followed by a patch test with the culprit drug after recovery. We discuss the diagnostic drug allergy evaluation and treatment approach.

A 37-year-old man presented with a 15-year history of severe psoriasis with frequent flares. He was treated with various topical and systemic agents including acitretin and methotrexate at 4-year intervals. Despite the addition of phototherapy, he underwent a new treatment with anti–TNF-α, as the disease control with other treatments was insufficient. Before starting anti–TNF-α, preventive treatment against TB with INH (300 mg/d) was indicated with 20 mm of purified protein derivative. On approximately the 20th day of treatment, he developed pruritic erythema with desquamation and exfoliation localized to the hands and feet (Figure 1). Isoniazid was discontinued and a topical steroid was initiated. After 3 weeks, the skin lesions were completely improved and INH was reinitiated at the same dose with antihistamine prophylaxis (oral levocetirizine 5 mg/d). Seven days later, similar skin lesions presented that were more extensive on the arms and legs (Figure 2). Complete blood cell counts, renal and hepatic function tests, and hepatitis markers were within reference range in consultation with the allergy division. To distinguish the lesions from a psoriasis attack, a punch biopsy of the eruptive dermatitis showed erythema multiforme–like dermatitis including dermal edema and perivascular lymphocytic infiltration with no relation to psoriasis but consistent with a drug eruption. Isoniazid was discontinued, and the skin lesions resolved after 4 weeks of topical steroid and oral antihistamine use (Figure 3). There was no other drug use except INH, and a skin patch test with INH was positive at 72 hours (Figure 4). Skin tests with INH were done to 5 healthy lesions that were negative. Finally, TB prophylaxis was performed with rifampicin (10 mg/kg/d [600 mg/d]) for 4 months with no ADRs. The patient’s psoriasis lesions improved with anti–TNF-α that was initiated 1 month after starting TB prevention with rifampicin.

This case of erythema multiforme–like dermatitis was diagnosed with acral involvement, a positive patch test to INH, and lymphocytic inflammation in a skin biopsy. It was a drug-induced reaction, as skin lesions developed during INH intake and improved after drug withdrawal.

Isoniazid, also known as isonicotinylhydrazide, is an oral antibiotic used for the treatment of TB and other mycobacteria. Protective treatment against latent TB primarily is done with daily INH for 6 or 9 months; alternatively, INH may be taken weekly with rifapentine for 3 months or daily with rifampicin for 4 months. Daily rifampicin alone for 4 months also is an option. In general, these regimens have similar efficacy; however, in terms of safety, the rifampicin and rifapentine combination regimens have fewer hepatotoxicity events compared to the INH alone regimen, but there are more cutaneous and flulike reactions and gastrointestinal intolerance.⁴ Cutaneous ADRs to TB treatment such as mild itchiness and cutaneous eruptions usually are observed within 2 months of drug initiation. Pyrazinamide was reported as the most common drug associated with cutaneous ADRs, and INH was the rarest offending drug.⁵

The frequency of ADRs to INH is approximately 5.4%, and the most prevalent ADRs include asymptomatic elevation of serum liver enzyme concentrations, peripheral neuropathy, and hepatotoxicity, and skin lesions are less common.² Our patient’s laboratory test results excluded vitamin B deficiency, hepatic and renal dysfunction, and neuropathy.

Previously reported skin reactions related to INH were late-type reactions such as maculopapular rash, dermatitis, erythema multiforme, drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, Stevens-Johnson syndrome, and toxic epidermal necrolysis.^5,6 The concerning prediagnosis of psoriatic exacerbation in our patient was ruled out by the absence of typical skin lesions such as well-defined, erythematous plaques and pustules and atypical localization such as the dorsal hands and feet rather than the knees, elbows, lumbosacral region, scalp, and abdomen, which is typical of psoriasis. DRESS syndrome was unlikely with the absence of fever, lymphadenopathy, hypereosinophilia, leukocytosis, and renal and hepatic dysfunction.⁷ There were no widespread blisters, epidermal detachment, or mucosal involvement on the trunk or face typically associated with Stevens-Johnson syndrome and toxic epidermal necrolysis.^7,8 A possible diagnosis of contact dermatitis was suspected with likely skin lesions as exfoliation and chapping, typical localization on the hands and feet, and positive patch test that supported sensitization to the drug. However, the patient’s skin lesions were not eczematous (characterized by erythema, vesiculation, exudation, or bullous edema in the acute phase), and were not localized to areas of irritant exposure.³ In our patient, erythematoedematous lesions in an acral distribution with no mucosal involvement and systemic exposure to INH was compatible with erythema multiforme, whereas the absence of target appearance, positive patch test, and late appearance were incompatible with erythema multiforme.⁸

Because the clinical picture did not fit contact dermatitis or erythema multiforme, a diagnosis of erythema multiforme–like noneczematous dermatitis was suggested. Noneczematous dermatitis has subtypes that include purpuric, lichenoid, pustular, lymphomatoid, dyshidrosiform, and pigmented, as well as erythema multiforme–like contact eruptions.⁹ These clinical entities are not associated with contact exposure, but are related to systemic exposure, as seen in our patient.¹⁰ The patch test positivity and skin biopsy report also supported the diagnosis of erythema multiforme–like dermatitis. Erythema multiforme–like dermatitis is thought to be caused by medications or infections inducing immunocomplexes and lymphocytic infiltration in the dermis and subepidermis. Nevertheless, the prognosis was self-limiting in both.⁸ The clinical polymorphism caused by INH in this patient was suggested to be related with individual susceptibility, variability of contact-activating modalities, and the targeted cutaneous structures. Furthermore, among the risk factors for cutaneous ADRs—HIV, polypharmacy, older age, and preexisting renal and liver impairment—the only notable factor in this patient was psoriasis as an autoimmune disorder.

Patients with skin diseases such as psoriasis should be followed up by closer monitoring during INH use. Withdrawal of the drug and symptomatic treatment of the lesions with corticosteroid and antihistamine are the first steps of drug intolerance. After complete recovery and termination of antiallergic drugs, diagnostic tests are recommended if the drug reaction was not life-threatening. Skin prick and intradermal tests are useful in early-type drug reactions, whereas patch testing and late evaluation of an intradermal test may be helpful in the diagnosis of delayed-type reactions. The full dose of INH is avoided in an intradermal test against irritation. A patch test with INH was performed by diluting a 100-mg tablet with 1 mL of distilled water, and used as 1/100, 1/10, and 1/1 dilutions.⁸ Patch testing with INH also was done in 5 healthy control patients to exclude the irritation effect in this case. The rechallenge of INH was done in a controlled manner in our patient to rule out psoriasis activation since it was a localized skin reaction with no serious ADR. An oral provocation test with the culprit drug is the gold standard of drug allergy diagnosis that should be done in a tertiary hospital with an intensive care unit.

This case of erythema multiforme–like dermatitis due to INH is interesting due to systemic intake of INH, which resulted in dermatitis with localized involvement similar to erythema multiforme but with no immunologic processes or prior sensitization. With the increasing use of anti–TNF-α treatment, INH use will be more prevalent than in the past for the treatment of latent TB. Even though the skin-restricted ADRs of INH are rare and minor, particular attention should be paid to patients with dermatologic diseases. In our case, diagnostic drug allergy evaluation was performed to optimize the second-line treatment of TB infection, in addition to early withdrawal of the culprit drug.

To the Editor:

Psoriasis vulgaris is a chronic autoimmune inflammatory disease and biologic agents, such as anti–tumor necrosis factor α (TNF-α), are alternative drugs in case of resistance or adverse events to conventional ones.¹ The limitation of these agents is immunosuppression that may cause infections such as tuberculosis (TB). Prophylaxis is indicated to latent TB diseases if the purified protein derivative (tuberculin) skin test is higher than 5 mm before starting these treatments. The challenge in TB treatment is adverse drug reactions (ADRs) that are reported in 4% to 6% of cases.^2,3

Erythema multiforme–like dermatitis is a rare skin rash that develops due to isoniazid (INH). The clinical presentation includes erythematoedematous lesions in an acral distribution with no mucosal involvement and systemic exposure to INH. Skin biopsy and patch tests are the supportive diagnostic methods. Isoniazid-associated skin rashes rarely are reported and generally are not severe enough to terminate the drug. We present a patient with psoriasis who received TB prophylaxis before anti–TNF-α use. He presented with erythema multiforme–like dermatitis due to INH. Withdrawal of the drug and treatment of the lesions were the first steps of intolerance, followed by a patch test with the culprit drug after recovery. We discuss the diagnostic drug allergy evaluation and treatment approach.

A 37-year-old man presented with a 15-year history of severe psoriasis with frequent flares. He was treated with various topical and systemic agents including acitretin and methotrexate at 4-year intervals. Despite the addition of phototherapy, he underwent a new treatment with anti–TNF-α, as the disease control with other treatments was insufficient. Before starting anti–TNF-α, preventive treatment against TB with INH (300 mg/d) was indicated with 20 mm of purified protein derivative. On approximately the 20th day of treatment, he developed pruritic erythema with desquamation and exfoliation localized to the hands and feet (Figure 1). Isoniazid was discontinued and a topical steroid was initiated. After 3 weeks, the skin lesions were completely improved and INH was reinitiated at the same dose with antihistamine prophylaxis (oral levocetirizine 5 mg/d). Seven days later, similar skin lesions presented that were more extensive on the arms and legs (Figure 2). Complete blood cell counts, renal and hepatic function tests, and hepatitis markers were within reference range in consultation with the allergy division. To distinguish the lesions from a psoriasis attack, a punch biopsy of the eruptive dermatitis showed erythema multiforme–like dermatitis including dermal edema and perivascular lymphocytic infiltration with no relation to psoriasis but consistent with a drug eruption. Isoniazid was discontinued, and the skin lesions resolved after 4 weeks of topical steroid and oral antihistamine use (Figure 3). There was no other drug use except INH, and a skin patch test with INH was positive at 72 hours (Figure 4). Skin tests with INH were done to 5 healthy lesions that were negative. Finally, TB prophylaxis was performed with rifampicin (10 mg/kg/d [600 mg/d]) for 4 months with no ADRs. The patient’s psoriasis lesions improved with anti–TNF-α that was initiated 1 month after starting TB prevention with rifampicin.

This case of erythema multiforme–like dermatitis was diagnosed with acral involvement, a positive patch test to INH, and lymphocytic inflammation in a skin biopsy. It was a drug-induced reaction, as skin lesions developed during INH intake and improved after drug withdrawal.

Isoniazid, also known as isonicotinylhydrazide, is an oral antibiotic used for the treatment of TB and other mycobacteria. Protective treatment against latent TB primarily is done with daily INH for 6 or 9 months; alternatively, INH may be taken weekly with rifapentine for 3 months or daily with rifampicin for 4 months. Daily rifampicin alone for 4 months also is an option. In general, these regimens have similar efficacy; however, in terms of safety, the rifampicin and rifapentine combination regimens have fewer hepatotoxicity events compared to the INH alone regimen, but there are more cutaneous and flulike reactions and gastrointestinal intolerance.⁴ Cutaneous ADRs to TB treatment such as mild itchiness and cutaneous eruptions usually are observed within 2 months of drug initiation. Pyrazinamide was reported as the most common drug associated with cutaneous ADRs, and INH was the rarest offending drug.⁵

The frequency of ADRs to INH is approximately 5.4%, and the most prevalent ADRs include asymptomatic elevation of serum liver enzyme concentrations, peripheral neuropathy, and hepatotoxicity, and skin lesions are less common.² Our patient’s laboratory test results excluded vitamin B deficiency, hepatic and renal dysfunction, and neuropathy.

Previously reported skin reactions related to INH were late-type reactions such as maculopapular rash, dermatitis, erythema multiforme, drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, Stevens-Johnson syndrome, and toxic epidermal necrolysis.^5,6 The concerning prediagnosis of psoriatic exacerbation in our patient was ruled out by the absence of typical skin lesions such as well-defined, erythematous plaques and pustules and atypical localization such as the dorsal hands and feet rather than the knees, elbows, lumbosacral region, scalp, and abdomen, which is typical of psoriasis. DRESS syndrome was unlikely with the absence of fever, lymphadenopathy, hypereosinophilia, leukocytosis, and renal and hepatic dysfunction.⁷ There were no widespread blisters, epidermal detachment, or mucosal involvement on the trunk or face typically associated with Stevens-Johnson syndrome and toxic epidermal necrolysis.^7,8 A possible diagnosis of contact dermatitis was suspected with likely skin lesions as exfoliation and chapping, typical localization on the hands and feet, and positive patch test that supported sensitization to the drug. However, the patient’s skin lesions were not eczematous (characterized by erythema, vesiculation, exudation, or bullous edema in the acute phase), and were not localized to areas of irritant exposure.³ In our patient, erythematoedematous lesions in an acral distribution with no mucosal involvement and systemic exposure to INH was compatible with erythema multiforme, whereas the absence of target appearance, positive patch test, and late appearance were incompatible with erythema multiforme.⁸

Because the clinical picture did not fit contact dermatitis or erythema multiforme, a diagnosis of erythema multiforme–like noneczematous dermatitis was suggested. Noneczematous dermatitis has subtypes that include purpuric, lichenoid, pustular, lymphomatoid, dyshidrosiform, and pigmented, as well as erythema multiforme–like contact eruptions.⁹ These clinical entities are not associated with contact exposure, but are related to systemic exposure, as seen in our patient.¹⁰ The patch test positivity and skin biopsy report also supported the diagnosis of erythema multiforme–like dermatitis. Erythema multiforme–like dermatitis is thought to be caused by medications or infections inducing immunocomplexes and lymphocytic infiltration in the dermis and subepidermis. Nevertheless, the prognosis was self-limiting in both.⁸ The clinical polymorphism caused by INH in this patient was suggested to be related with individual susceptibility, variability of contact-activating modalities, and the targeted cutaneous structures. Furthermore, among the risk factors for cutaneous ADRs—HIV, polypharmacy, older age, and preexisting renal and liver impairment—the only notable factor in this patient was psoriasis as an autoimmune disorder.

Patients with skin diseases such as psoriasis should be followed up by closer monitoring during INH use. Withdrawal of the drug and symptomatic treatment of the lesions with corticosteroid and antihistamine are the first steps of drug intolerance. After complete recovery and termination of antiallergic drugs, diagnostic tests are recommended if the drug reaction was not life-threatening. Skin prick and intradermal tests are useful in early-type drug reactions, whereas patch testing and late evaluation of an intradermal test may be helpful in the diagnosis of delayed-type reactions. The full dose of INH is avoided in an intradermal test against irritation. A patch test with INH was performed by diluting a 100-mg tablet with 1 mL of distilled water, and used as 1/100, 1/10, and 1/1 dilutions.⁸ Patch testing with INH also was done in 5 healthy control patients to exclude the irritation effect in this case. The rechallenge of INH was done in a controlled manner in our patient to rule out psoriasis activation since it was a localized skin reaction with no serious ADR. An oral provocation test with the culprit drug is the gold standard of drug allergy diagnosis that should be done in a tertiary hospital with an intensive care unit.

This case of erythema multiforme–like dermatitis due to INH is interesting due to systemic intake of INH, which resulted in dermatitis with localized involvement similar to erythema multiforme but with no immunologic processes or prior sensitization. With the increasing use of anti–TNF-α treatment, INH use will be more prevalent than in the past for the treatment of latent TB. Even though the skin-restricted ADRs of INH are rare and minor, particular attention should be paid to patients with dermatologic diseases. In our case, diagnostic drug allergy evaluation was performed to optimize the second-line treatment of TB infection, in addition to early withdrawal of the culprit drug.

To the Editor:

The term tinea incognito was introduced by Ive and Marks¹ in 1968 and refers to unusual clinical presentations of tinea due to the application of topical corticosteroids. Tinea incognito, which does not feature the classical clinical characteristics of tinea corporis such as well-defined, erythematous, scaly patches and elevated borders, is regularly misdiagnosed as inflammatory dermatosis.² Immunosuppression caused by topical and/or systemic steroids predisposes patients to the development of tinea.³ Herein, a case of widespread pustular tinea incognito mimicking pustular psoriasis along with failure of tumor necrosis factor (TNF) inhibitor treatment is reported in a patient with chronic plaque psoriasis and steroid-induced Cushing syndrome.

A 46-year-old man with a 25-year history of psoriasis was referred to the dermatologic outpatient clinic with a severe flare-up of chronic plaque psoriasis. Prior treatments included methotrexate and acitretin without response. Narrowband UVB treatment was discontinued due to claustrophobia. Topical treatment with calcipotriol 0.005%–betamethasone dipropionate 0.05% gel was reported to be ineffective. The patient was administered prednisone over several months in a primary care setting at a dosage of 35 mg daily when he presented to the dermatology clinic. Physical examination revealed widespread chronic plaque psoriasis of the trunk and extremities, and a psoriasis area and severity index score of 15 was calculated. The patient had onychodystrophy with subungual hyperkeratosis of all toenails. Signs of prednisone-induced Cushing syndrome, including central obesity, lipodystrophy, and red striae, were noted.

Treatment was started by dermatology with the TNF inhibitor adalimumab at an initial dose of 80 mg, followed by subsequent 40-mg doses every other week; prednisone was tapered off. Topical treatment with a 4-week course of clobetasol propionate cream 0.05% daily for psoriatic lesions was initiated.

Six weeks after the initial consultation, the patient presented to the hospital’s emergency department with worsening symptoms of itchy, burning, and painful skin after good initial improvement. The patient’s skin started to burn upon application of clobetasol and the rash worsened. The patient did not use emollients. At that point, the patient was on a daily dose of 15 mg of prednisone. On dermatologic review, multiple partially annular lesions with subtle scaling and multiple pustules on the arms and legs as well as the buttocks and groin were noticed. These lesions were confined to sites of prior psoriasis as marked by postinflammatory hyperpigmentation (Figure 1). Widespread tinea was assumed, and treatment with fluconazole 50 mg daily was administered for 4 weeks. Direct examination of skin scrapings from the patient’s thigh showed hyphae, and fungal culture was positive for Trichophyton rubrum. Scrapings from the patient’s hallux nail remained inconclusive due to bacterial overgrowth. At 4-week follow-up, the patient’s skin had cleared entirely and showed only postinflammatory changes (Figure 2). Healthy proximal nail growth was observed. Fluconazole was continued at a once-weekly dose of 150 mg together with adalimumab at a dose of 40 mg every 2 weeks and a prednisone tapering schedule.

Apart from psoriasis, tinea incognito most commonly is mistaken for other inflammatory conditions such as eczema, folliculitis, rosacea, granuloma annulare, and discoid lupus erythematosus.² Inflammatory tinea can present with pustules due to the increased occurrence of neutrophil invasion.¹¹This patient’s symptoms worsened 4 weeks after the initiation of TNF inhibitor treatment, which suggested treatment failure. However, clearance of the preexisting psoriatic lesions with remnant hyperpigmentation only argued for good response to TNF inhibitor treatment. The main differential diagnosis of this case of tinea incognito was generalized pustular psoriasis. The patient also was being treated with systemic and topical steroids, both known for their potential to trigger pustular psoriasis.^12,13 Furthermore, TNF inhibitors have been described as a trigger for predominantly palmoplantar pustulosis but also are additionally associated with generalized pustular psoriasis.¹⁴

This case aims to raise awareness that tinea incognito can imitate both pustular psoriasis and TNF inhibitor treatment failure. Furthermore, the presented findings highlight risks associated with the treatment of psoriasis with systemic steroids. Pustular tinea incognito should be considered in the differential diagnosis of pustular psoriasis, especially in the setting of immunosuppression. After initial improvement, worsening of symptoms such as itching and burning as well as extension of the lesions upon application of topical steroids are regularly described in tinea incognito and can be present in addition to the more typical annular presentation of lesions as a clue to the diagnosis.

To the Editor:

The term tinea incognito was introduced by Ive and Marks¹ in 1968 and refers to unusual clinical presentations of tinea due to the application of topical corticosteroids. Tinea incognito, which does not feature the classical clinical characteristics of tinea corporis such as well-defined, erythematous, scaly patches and elevated borders, is regularly misdiagnosed as inflammatory dermatosis.² Immunosuppression caused by topical and/or systemic steroids predisposes patients to the development of tinea.³ Herein, a case of widespread pustular tinea incognito mimicking pustular psoriasis along with failure of tumor necrosis factor (TNF) inhibitor treatment is reported in a patient with chronic plaque psoriasis and steroid-induced Cushing syndrome.

A 46-year-old man with a 25-year history of psoriasis was referred to the dermatologic outpatient clinic with a severe flare-up of chronic plaque psoriasis. Prior treatments included methotrexate and acitretin without response. Narrowband UVB treatment was discontinued due to claustrophobia. Topical treatment with calcipotriol 0.005%–betamethasone dipropionate 0.05% gel was reported to be ineffective. The patient was administered prednisone over several months in a primary care setting at a dosage of 35 mg daily when he presented to the dermatology clinic. Physical examination revealed widespread chronic plaque psoriasis of the trunk and extremities, and a psoriasis area and severity index score of 15 was calculated. The patient had onychodystrophy with subungual hyperkeratosis of all toenails. Signs of prednisone-induced Cushing syndrome, including central obesity, lipodystrophy, and red striae, were noted.

Treatment was started by dermatology with the TNF inhibitor adalimumab at an initial dose of 80 mg, followed by subsequent 40-mg doses every other week; prednisone was tapered off. Topical treatment with a 4-week course of clobetasol propionate cream 0.05% daily for psoriatic lesions was initiated.

Six weeks after the initial consultation, the patient presented to the hospital’s emergency department with worsening symptoms of itchy, burning, and painful skin after good initial improvement. The patient’s skin started to burn upon application of clobetasol and the rash worsened. The patient did not use emollients. At that point, the patient was on a daily dose of 15 mg of prednisone. On dermatologic review, multiple partially annular lesions with subtle scaling and multiple pustules on the arms and legs as well as the buttocks and groin were noticed. These lesions were confined to sites of prior psoriasis as marked by postinflammatory hyperpigmentation (Figure 1). Widespread tinea was assumed, and treatment with fluconazole 50 mg daily was administered for 4 weeks. Direct examination of skin scrapings from the patient’s thigh showed hyphae, and fungal culture was positive for Trichophyton rubrum. Scrapings from the patient’s hallux nail remained inconclusive due to bacterial overgrowth. At 4-week follow-up, the patient’s skin had cleared entirely and showed only postinflammatory changes (Figure 2). Healthy proximal nail growth was observed. Fluconazole was continued at a once-weekly dose of 150 mg together with adalimumab at a dose of 40 mg every 2 weeks and a prednisone tapering schedule.

Apart from psoriasis, tinea incognito most commonly is mistaken for other inflammatory conditions such as eczema, folliculitis, rosacea, granuloma annulare, and discoid lupus erythematosus.² Inflammatory tinea can present with pustules due to the increased occurrence of neutrophil invasion.¹¹This patient’s symptoms worsened 4 weeks after the initiation of TNF inhibitor treatment, which suggested treatment failure. However, clearance of the preexisting psoriatic lesions with remnant hyperpigmentation only argued for good response to TNF inhibitor treatment. The main differential diagnosis of this case of tinea incognito was generalized pustular psoriasis. The patient also was being treated with systemic and topical steroids, both known for their potential to trigger pustular psoriasis.^12,13 Furthermore, TNF inhibitors have been described as a trigger for predominantly palmoplantar pustulosis but also are additionally associated with generalized pustular psoriasis.¹⁴

This case aims to raise awareness that tinea incognito can imitate both pustular psoriasis and TNF inhibitor treatment failure. Furthermore, the presented findings highlight risks associated with the treatment of psoriasis with systemic steroids. Pustular tinea incognito should be considered in the differential diagnosis of pustular psoriasis, especially in the setting of immunosuppression. After initial improvement, worsening of symptoms such as itching and burning as well as extension of the lesions upon application of topical steroids are regularly described in tinea incognito and can be present in addition to the more typical annular presentation of lesions as a clue to the diagnosis.

To the Editor:

The term tinea incognito was introduced by Ive and Marks¹ in 1968 and refers to unusual clinical presentations of tinea due to the application of topical corticosteroids. Tinea incognito, which does not feature the classical clinical characteristics of tinea corporis such as well-defined, erythematous, scaly patches and elevated borders, is regularly misdiagnosed as inflammatory dermatosis.² Immunosuppression caused by topical and/or systemic steroids predisposes patients to the development of tinea.³ Herein, a case of widespread pustular tinea incognito mimicking pustular psoriasis along with failure of tumor necrosis factor (TNF) inhibitor treatment is reported in a patient with chronic plaque psoriasis and steroid-induced Cushing syndrome.

A 46-year-old man with a 25-year history of psoriasis was referred to the dermatologic outpatient clinic with a severe flare-up of chronic plaque psoriasis. Prior treatments included methotrexate and acitretin without response. Narrowband UVB treatment was discontinued due to claustrophobia. Topical treatment with calcipotriol 0.005%–betamethasone dipropionate 0.05% gel was reported to be ineffective. The patient was administered prednisone over several months in a primary care setting at a dosage of 35 mg daily when he presented to the dermatology clinic. Physical examination revealed widespread chronic plaque psoriasis of the trunk and extremities, and a psoriasis area and severity index score of 15 was calculated. The patient had onychodystrophy with subungual hyperkeratosis of all toenails. Signs of prednisone-induced Cushing syndrome, including central obesity, lipodystrophy, and red striae, were noted.

Treatment was started by dermatology with the TNF inhibitor adalimumab at an initial dose of 80 mg, followed by subsequent 40-mg doses every other week; prednisone was tapered off. Topical treatment with a 4-week course of clobetasol propionate cream 0.05% daily for psoriatic lesions was initiated.

Six weeks after the initial consultation, the patient presented to the hospital’s emergency department with worsening symptoms of itchy, burning, and painful skin after good initial improvement. The patient’s skin started to burn upon application of clobetasol and the rash worsened. The patient did not use emollients. At that point, the patient was on a daily dose of 15 mg of prednisone. On dermatologic review, multiple partially annular lesions with subtle scaling and multiple pustules on the arms and legs as well as the buttocks and groin were noticed. These lesions were confined to sites of prior psoriasis as marked by postinflammatory hyperpigmentation (Figure 1). Widespread tinea was assumed, and treatment with fluconazole 50 mg daily was administered for 4 weeks. Direct examination of skin scrapings from the patient’s thigh showed hyphae, and fungal culture was positive for Trichophyton rubrum. Scrapings from the patient’s hallux nail remained inconclusive due to bacterial overgrowth. At 4-week follow-up, the patient’s skin had cleared entirely and showed only postinflammatory changes (Figure 2). Healthy proximal nail growth was observed. Fluconazole was continued at a once-weekly dose of 150 mg together with adalimumab at a dose of 40 mg every 2 weeks and a prednisone tapering schedule.

Apart from psoriasis, tinea incognito most commonly is mistaken for other inflammatory conditions such as eczema, folliculitis, rosacea, granuloma annulare, and discoid lupus erythematosus.² Inflammatory tinea can present with pustules due to the increased occurrence of neutrophil invasion.¹¹This patient’s symptoms worsened 4 weeks after the initiation of TNF inhibitor treatment, which suggested treatment failure. However, clearance of the preexisting psoriatic lesions with remnant hyperpigmentation only argued for good response to TNF inhibitor treatment. The main differential diagnosis of this case of tinea incognito was generalized pustular psoriasis. The patient also was being treated with systemic and topical steroids, both known for their potential to trigger pustular psoriasis.^12,13 Furthermore, TNF inhibitors have been described as a trigger for predominantly palmoplantar pustulosis but also are additionally associated with generalized pustular psoriasis.¹⁴

This case aims to raise awareness that tinea incognito can imitate both pustular psoriasis and TNF inhibitor treatment failure. Furthermore, the presented findings highlight risks associated with the treatment of psoriasis with systemic steroids. Pustular tinea incognito should be considered in the differential diagnosis of pustular psoriasis, especially in the setting of immunosuppression. After initial improvement, worsening of symptoms such as itching and burning as well as extension of the lesions upon application of topical steroids are regularly described in tinea incognito and can be present in addition to the more typical annular presentation of lesions as a clue to the diagnosis.

The Diagnosis: Seborrheic Keratosis-like Melanoma 

Seborrheic keratosis (SK) is a benign neoplasm commonly encountered on the skin and frequently diagnosed by clinical examination alone. Seborrheic keratosis-like melanomas are melanomas that clinically or dermatoscopically resemble SKs and thus can be challenging to accurately diagnose. Melanomas can have a hyperkeratotic or verrucous appearance^1-3 and can even exhibit dermatoscopic and microscopic features that are found in SKs such as comedolike openings and milialike cysts as well as acanthosis and pseudohorn cysts, respectively.²  

In our patient, histopathology revealed SK-like architecture with hyperorthokeratosis, papillomatosis, pseudohorn cyst formation, and basaloid acanthosis (Figure). However, within the lesion was an asymmetric proliferation of nested atypical melanocytes with melanin pigment production. The atypical melanocytes filled and expanded papillomatous projections without notable pagetoid growth and extended into the dermis. There was a background congenital nevus component. These findings were diagnostic of invasive malignant melanoma, extending to a Breslow depth of 5.5 mm. A follow-up sentinel lymph node biopsy was negative for metastatic melanoma. The clinical and histologic findings did not show melanoma in the surrounding skin to suggest colonization of an SK by an adjacent melanoma. The clinical history of a long-standing lesion in conjunction with a congenital nevus component on histology favored a diagnosis of melanoma arising in association with a congenital nevus with an SK-like architecture rather than arising in a preexisting SK or de novo melanoma.  

Because our patient did not have multiple widespread SKs and reported rapid growth in the lesion in the last 6 months, there was concern for a malignant neoplasm. However, in patients with numerous SKs or areas of chronically sun-damaged skin, it can be difficult to identify suspicious lesions. It is important for clinicians to remain aware of SK-like melanomas and have a lower threshold for biopsy of any changing or symptomatic lesion that clinically resembles an SK. In our case, the history of change and the markedly different clinical appearance of the lesion in comparison to our patient's SKs prompted the biopsy. Criteria have been proposed to help differentiate these entities under dermoscopy, with melanoma showing the presence of the blue-black sign, pigment network, pseudopods or streaks, and/or the blue-white veil.⁴ 

Cutaneous metastases classically present as dermal nodules, plaques, or ulcers.^5,6 A rare pigmented case of metastatic breast adenocarcinoma clinically mimicking melanoma has been reported.⁷ There is limited literature on the dermoscopic features of cutaneous metastases, but it appears that polymorphic vascular patterns are most common.^5,8 The possibility of a metastatic melanoma involving an SK is a theoretical consideration, but there was no prior history of melanoma in our patient, and the histologic findings were consistent with primary melanoma. There was no histologic evidence of pigmented metastatic breast carcinoma or metastatic lung carcinoma.  

Pigmented malignant hidroacanthoma simplex and pigmented porocarcinomas are rare malignant sweat gland tumors.^9-11 Their benign counterparts are the more commonly encountered hidroacanthoma simplex (intraepidermal poroma) and poroma. Pigmented malignant hidroacanthoma simplex has been reported to clinically mimic an irritated SK.¹⁰ The histopathology of our case did not have features of malignant hidroacanthoma simplex or porocarcinoma. Pigmented squamous cell carcinoma is an uncommon variant of squamous cell carcinoma, and histopathology would reveal proliferation of atypical keratinocytes.¹²  

The Diagnosis: Seborrheic Keratosis-like Melanoma 

Seborrheic keratosis (SK) is a benign neoplasm commonly encountered on the skin and frequently diagnosed by clinical examination alone. Seborrheic keratosis-like melanomas are melanomas that clinically or dermatoscopically resemble SKs and thus can be challenging to accurately diagnose. Melanomas can have a hyperkeratotic or verrucous appearance^1-3 and can even exhibit dermatoscopic and microscopic features that are found in SKs such as comedolike openings and milialike cysts as well as acanthosis and pseudohorn cysts, respectively.²  

In our patient, histopathology revealed SK-like architecture with hyperorthokeratosis, papillomatosis, pseudohorn cyst formation, and basaloid acanthosis (Figure). However, within the lesion was an asymmetric proliferation of nested atypical melanocytes with melanin pigment production. The atypical melanocytes filled and expanded papillomatous projections without notable pagetoid growth and extended into the dermis. There was a background congenital nevus component. These findings were diagnostic of invasive malignant melanoma, extending to a Breslow depth of 5.5 mm. A follow-up sentinel lymph node biopsy was negative for metastatic melanoma. The clinical and histologic findings did not show melanoma in the surrounding skin to suggest colonization of an SK by an adjacent melanoma. The clinical history of a long-standing lesion in conjunction with a congenital nevus component on histology favored a diagnosis of melanoma arising in association with a congenital nevus with an SK-like architecture rather than arising in a preexisting SK or de novo melanoma.  

Because our patient did not have multiple widespread SKs and reported rapid growth in the lesion in the last 6 months, there was concern for a malignant neoplasm. However, in patients with numerous SKs or areas of chronically sun-damaged skin, it can be difficult to identify suspicious lesions. It is important for clinicians to remain aware of SK-like melanomas and have a lower threshold for biopsy of any changing or symptomatic lesion that clinically resembles an SK. In our case, the history of change and the markedly different clinical appearance of the lesion in comparison to our patient's SKs prompted the biopsy. Criteria have been proposed to help differentiate these entities under dermoscopy, with melanoma showing the presence of the blue-black sign, pigment network, pseudopods or streaks, and/or the blue-white veil.⁴ 

Cutaneous metastases classically present as dermal nodules, plaques, or ulcers.^5,6 A rare pigmented case of metastatic breast adenocarcinoma clinically mimicking melanoma has been reported.⁷ There is limited literature on the dermoscopic features of cutaneous metastases, but it appears that polymorphic vascular patterns are most common.^5,8 The possibility of a metastatic melanoma involving an SK is a theoretical consideration, but there was no prior history of melanoma in our patient, and the histologic findings were consistent with primary melanoma. There was no histologic evidence of pigmented metastatic breast carcinoma or metastatic lung carcinoma.  

Pigmented malignant hidroacanthoma simplex and pigmented porocarcinomas are rare malignant sweat gland tumors.^9-11 Their benign counterparts are the more commonly encountered hidroacanthoma simplex (intraepidermal poroma) and poroma. Pigmented malignant hidroacanthoma simplex has been reported to clinically mimic an irritated SK.¹⁰ The histopathology of our case did not have features of malignant hidroacanthoma simplex or porocarcinoma. Pigmented squamous cell carcinoma is an uncommon variant of squamous cell carcinoma, and histopathology would reveal proliferation of atypical keratinocytes.¹²  

The Diagnosis: Seborrheic Keratosis-like Melanoma 

Seborrheic keratosis (SK) is a benign neoplasm commonly encountered on the skin and frequently diagnosed by clinical examination alone. Seborrheic keratosis-like melanomas are melanomas that clinically or dermatoscopically resemble SKs and thus can be challenging to accurately diagnose. Melanomas can have a hyperkeratotic or verrucous appearance^1-3 and can even exhibit dermatoscopic and microscopic features that are found in SKs such as comedolike openings and milialike cysts as well as acanthosis and pseudohorn cysts, respectively.²  

In our patient, histopathology revealed SK-like architecture with hyperorthokeratosis, papillomatosis, pseudohorn cyst formation, and basaloid acanthosis (Figure). However, within the lesion was an asymmetric proliferation of nested atypical melanocytes with melanin pigment production. The atypical melanocytes filled and expanded papillomatous projections without notable pagetoid growth and extended into the dermis. There was a background congenital nevus component. These findings were diagnostic of invasive malignant melanoma, extending to a Breslow depth of 5.5 mm. A follow-up sentinel lymph node biopsy was negative for metastatic melanoma. The clinical and histologic findings did not show melanoma in the surrounding skin to suggest colonization of an SK by an adjacent melanoma. The clinical history of a long-standing lesion in conjunction with a congenital nevus component on histology favored a diagnosis of melanoma arising in association with a congenital nevus with an SK-like architecture rather than arising in a preexisting SK or de novo melanoma.  

Because our patient did not have multiple widespread SKs and reported rapid growth in the lesion in the last 6 months, there was concern for a malignant neoplasm. However, in patients with numerous SKs or areas of chronically sun-damaged skin, it can be difficult to identify suspicious lesions. It is important for clinicians to remain aware of SK-like melanomas and have a lower threshold for biopsy of any changing or symptomatic lesion that clinically resembles an SK. In our case, the history of change and the markedly different clinical appearance of the lesion in comparison to our patient's SKs prompted the biopsy. Criteria have been proposed to help differentiate these entities under dermoscopy, with melanoma showing the presence of the blue-black sign, pigment network, pseudopods or streaks, and/or the blue-white veil.⁴ 

Cutaneous metastases classically present as dermal nodules, plaques, or ulcers.^5,6 A rare pigmented case of metastatic breast adenocarcinoma clinically mimicking melanoma has been reported.⁷ There is limited literature on the dermoscopic features of cutaneous metastases, but it appears that polymorphic vascular patterns are most common.^5,8 The possibility of a metastatic melanoma involving an SK is a theoretical consideration, but there was no prior history of melanoma in our patient, and the histologic findings were consistent with primary melanoma. There was no histologic evidence of pigmented metastatic breast carcinoma or metastatic lung carcinoma.  

Pigmented malignant hidroacanthoma simplex and pigmented porocarcinomas are rare malignant sweat gland tumors.^9-11 Their benign counterparts are the more commonly encountered hidroacanthoma simplex (intraepidermal poroma) and poroma. Pigmented malignant hidroacanthoma simplex has been reported to clinically mimic an irritated SK.¹⁰ The histopathology of our case did not have features of malignant hidroacanthoma simplex or porocarcinoma. Pigmented squamous cell carcinoma is an uncommon variant of squamous cell carcinoma, and histopathology would reveal proliferation of atypical keratinocytes.¹²  

Studding almost every inch of skin except the face are gray lichenified plaques coating a patient’s body like worn leather. Raking his nails across his arm, the patient reminds me how long he had waited to receive this referral and how early he had awoken for this appointment. He was well acquainted with the value of promptness; in his world, it might make the difference between sleeping on a cot and a night spent on concrete.

Over the last year, the patient had cycled through the few safety-net clinics scattered throughout the city. He had accumulated numerous different diagnoses from atopic dermatitis to disseminated tinea corporis. A few minutes, one #15 scalpel, and mineral oil were all it took for us to unravel the mystery. As the attending and I peered through the microscope at the scabies ovum, I couldn’t help but wonder about the alternative outcomes to his case. Left untreated, scabies compromises the skin barrier, paving the way for secondary infections such as cellulitis. Depending on the pathogen, this infection may in turn evolve into acute postinfectious glomerulonephritis.^1-4 An elusive diagnosis can quietly escalate into considerable morbidity for patients. This case highlights the dire consequences of dermatologic health disparities and places medicine’s primordial function into sharp focus: the alleviation of suffering.

The Dermatologic Burden of Disease

As a major contributor to global disease burden, dermatologic disease is the fourth greatest cause of disability worldwide when mortality is factored out.^5,6 Among global rural populations, dermatologic disease constitutes one of the leading causes of death and/or loss of professional capabilities.⁷ In the United States alone, nearly 27% of the population saw a physician for at least 1 dermatologic disease in 2013.⁵ The tremendous prevalence of skin disease magnifies discrepancies in access to dermatologic care, which has been observed to be influenced by age, socioeconomic background, rurality, and sex.⁸

There has been growing focus on the national shortage of dermatologists over the last 2 decades.^9,10 With an aging population and rising incidence of skin cancer, this undersupply is projected to increase and disproportionately impact ethnic minorities as well as those from socioeconomically disadvantaged backgrounds.^8,9,11-14 These trends are of particular importance to residents and medical trainees. Multiple studies have demonstrated that the patient demographic of hospital-based resident clinics includes primarily minority and disenfranchised populations with poorer overall health.^15-17 In contrast to faculty clinics, residents treat patients who are more likely to be nonwhite and more likely to be reimbursed by Medicaid.¹⁸ The unique demographic makeup of hospital-based resident clinics raises questions about the preparedness and comfort of resident physicians in managing the nuances of health care delivery in these settings.¹⁰

Providing equitable care to marginalized populations within the constraints of 15- to 30-minute visits can be challenging to physicians and trainees. Even clinicians with the best of intentions may be impeded by a lack of familiarity with the daily realities of impoverished living conditions, implicit prejudice against people living in poverty, and adapting recommendations to varying levels of health literacy among patients.^19,20 Contending with these daunting obstacles can be discouraging. Given how entrenched certain institutional barriers are, questioning them may seem an exercise in futility, yet history demonstrates that residents can and have been empowered to improve tangible outcomes for vulnerable populations. In reflecting on approaches of the general medical education system, The Josiah Macy Jr. Foundation President George E. Thibault, MD, observed that, “When appropriately trained, deployed and incented, [residents] can help achieve institutional goals to improve quality, safety and efficiency.”²¹

Start Small But Dream Big

Action begins with awareness. Medical school and teaching hospital curricula are increasingly integrating educational exercises regarding the social determinants of health and populations with unmet needs. Medical training presents an exclusive opportunity to gain exposure to and familiarity with patient populations that one might not otherwise encounter. Immersion programs provide invaluable experience in tailoring health care delivery to the needs of vulnerable communities. Although opportunities for international rotations abound, domestic rotations among underserved populations can be just as transformative, including correctional medicine, homeless clinics, the Indian Health Service, and rural communities.

Create Partnerships to Broaden Impact of Service

Affecting the largest and most visible organ, skin disease often presents a substantial concern for patients and can herald systemic disease. The nature of dermatologic disease engenders close collaboration between general practitioners and specialists. For example, while resident-run or safety-net clinics characteristically center on providing holistic care for patients through internal medicine or primary care, these overworked and understaffed clinics often are in need of evaluation by specialists for specific concerns. Some clinic models feature dermatology faculty who volunteer routinely (ie, every 2 weeks, every month) to examine all the clinic’s patients presenting with concerns pertinent to the specialty. Drawing on their respective areas of expertise, general practitioners and dermatologists therefore can collaborate to connect disadvantaged patients with the specialized care they need.

Challenges Present Opportunities for Innovation

Adhering to the social distancing requirements of the COVID-19 pandemic protocol has driven clinicians to utilize innovative approaches to patient care. The rural-urban misdistribution of the dermatologist workforce has long been established, with rural patients often experiencing lengthy wait times to see a specialist.⁹ Both synchronous and asynchronous teledermatology modalities provide an ideal platform for triaging patients with dermatologic concerns who otherwise have meager access to a dermatologist.

Final Thoughts

Residency training is a prime opportunity to gain exposure to the broad spectrum of disease within dermatology as well as the diverse range of affected patients. Drawing on the aforementioned strategies, residents can leverage this knowledge in the service of underserved patients.

Studding almost every inch of skin except the face are gray lichenified plaques coating a patient’s body like worn leather. Raking his nails across his arm, the patient reminds me how long he had waited to receive this referral and how early he had awoken for this appointment. He was well acquainted with the value of promptness; in his world, it might make the difference between sleeping on a cot and a night spent on concrete.

Over the last year, the patient had cycled through the few safety-net clinics scattered throughout the city. He had accumulated numerous different diagnoses from atopic dermatitis to disseminated tinea corporis. A few minutes, one #15 scalpel, and mineral oil were all it took for us to unravel the mystery. As the attending and I peered through the microscope at the scabies ovum, I couldn’t help but wonder about the alternative outcomes to his case. Left untreated, scabies compromises the skin barrier, paving the way for secondary infections such as cellulitis. Depending on the pathogen, this infection may in turn evolve into acute postinfectious glomerulonephritis.^1-4 An elusive diagnosis can quietly escalate into considerable morbidity for patients. This case highlights the dire consequences of dermatologic health disparities and places medicine’s primordial function into sharp focus: the alleviation of suffering.

The Dermatologic Burden of Disease

As a major contributor to global disease burden, dermatologic disease is the fourth greatest cause of disability worldwide when mortality is factored out.^5,6 Among global rural populations, dermatologic disease constitutes one of the leading causes of death and/or loss of professional capabilities.⁷ In the United States alone, nearly 27% of the population saw a physician for at least 1 dermatologic disease in 2013.⁵ The tremendous prevalence of skin disease magnifies discrepancies in access to dermatologic care, which has been observed to be influenced by age, socioeconomic background, rurality, and sex.⁸

There has been growing focus on the national shortage of dermatologists over the last 2 decades.^9,10 With an aging population and rising incidence of skin cancer, this undersupply is projected to increase and disproportionately impact ethnic minorities as well as those from socioeconomically disadvantaged backgrounds.^8,9,11-14 These trends are of particular importance to residents and medical trainees. Multiple studies have demonstrated that the patient demographic of hospital-based resident clinics includes primarily minority and disenfranchised populations with poorer overall health.^15-17 In contrast to faculty clinics, residents treat patients who are more likely to be nonwhite and more likely to be reimbursed by Medicaid.¹⁸ The unique demographic makeup of hospital-based resident clinics raises questions about the preparedness and comfort of resident physicians in managing the nuances of health care delivery in these settings.¹⁰

Providing equitable care to marginalized populations within the constraints of 15- to 30-minute visits can be challenging to physicians and trainees. Even clinicians with the best of intentions may be impeded by a lack of familiarity with the daily realities of impoverished living conditions, implicit prejudice against people living in poverty, and adapting recommendations to varying levels of health literacy among patients.^19,20 Contending with these daunting obstacles can be discouraging. Given how entrenched certain institutional barriers are, questioning them may seem an exercise in futility, yet history demonstrates that residents can and have been empowered to improve tangible outcomes for vulnerable populations. In reflecting on approaches of the general medical education system, The Josiah Macy Jr. Foundation President George E. Thibault, MD, observed that, “When appropriately trained, deployed and incented, [residents] can help achieve institutional goals to improve quality, safety and efficiency.”²¹

Start Small But Dream Big

Action begins with awareness. Medical school and teaching hospital curricula are increasingly integrating educational exercises regarding the social determinants of health and populations with unmet needs. Medical training presents an exclusive opportunity to gain exposure to and familiarity with patient populations that one might not otherwise encounter. Immersion programs provide invaluable experience in tailoring health care delivery to the needs of vulnerable communities. Although opportunities for international rotations abound, domestic rotations among underserved populations can be just as transformative, including correctional medicine, homeless clinics, the Indian Health Service, and rural communities.

Create Partnerships to Broaden Impact of Service

Affecting the largest and most visible organ, skin disease often presents a substantial concern for patients and can herald systemic disease. The nature of dermatologic disease engenders close collaboration between general practitioners and specialists. For example, while resident-run or safety-net clinics characteristically center on providing holistic care for patients through internal medicine or primary care, these overworked and understaffed clinics often are in need of evaluation by specialists for specific concerns. Some clinic models feature dermatology faculty who volunteer routinely (ie, every 2 weeks, every month) to examine all the clinic’s patients presenting with concerns pertinent to the specialty. Drawing on their respective areas of expertise, general practitioners and dermatologists therefore can collaborate to connect disadvantaged patients with the specialized care they need.

Challenges Present Opportunities for Innovation

Adhering to the social distancing requirements of the COVID-19 pandemic protocol has driven clinicians to utilize innovative approaches to patient care. The rural-urban misdistribution of the dermatologist workforce has long been established, with rural patients often experiencing lengthy wait times to see a specialist.⁹ Both synchronous and asynchronous teledermatology modalities provide an ideal platform for triaging patients with dermatologic concerns who otherwise have meager access to a dermatologist.

Final Thoughts

Residency training is a prime opportunity to gain exposure to the broad spectrum of disease within dermatology as well as the diverse range of affected patients. Drawing on the aforementioned strategies, residents can leverage this knowledge in the service of underserved patients.

Studding almost every inch of skin except the face are gray lichenified plaques coating a patient’s body like worn leather. Raking his nails across his arm, the patient reminds me how long he had waited to receive this referral and how early he had awoken for this appointment. He was well acquainted with the value of promptness; in his world, it might make the difference between sleeping on a cot and a night spent on concrete.

Over the last year, the patient had cycled through the few safety-net clinics scattered throughout the city. He had accumulated numerous different diagnoses from atopic dermatitis to disseminated tinea corporis. A few minutes, one #15 scalpel, and mineral oil were all it took for us to unravel the mystery. As the attending and I peered through the microscope at the scabies ovum, I couldn’t help but wonder about the alternative outcomes to his case. Left untreated, scabies compromises the skin barrier, paving the way for secondary infections such as cellulitis. Depending on the pathogen, this infection may in turn evolve into acute postinfectious glomerulonephritis.^1-4 An elusive diagnosis can quietly escalate into considerable morbidity for patients. This case highlights the dire consequences of dermatologic health disparities and places medicine’s primordial function into sharp focus: the alleviation of suffering.

The Dermatologic Burden of Disease

As a major contributor to global disease burden, dermatologic disease is the fourth greatest cause of disability worldwide when mortality is factored out.^5,6 Among global rural populations, dermatologic disease constitutes one of the leading causes of death and/or loss of professional capabilities.⁷ In the United States alone, nearly 27% of the population saw a physician for at least 1 dermatologic disease in 2013.⁵ The tremendous prevalence of skin disease magnifies discrepancies in access to dermatologic care, which has been observed to be influenced by age, socioeconomic background, rurality, and sex.⁸

There has been growing focus on the national shortage of dermatologists over the last 2 decades.^9,10 With an aging population and rising incidence of skin cancer, this undersupply is projected to increase and disproportionately impact ethnic minorities as well as those from socioeconomically disadvantaged backgrounds.^8,9,11-14 These trends are of particular importance to residents and medical trainees. Multiple studies have demonstrated that the patient demographic of hospital-based resident clinics includes primarily minority and disenfranchised populations with poorer overall health.^15-17 In contrast to faculty clinics, residents treat patients who are more likely to be nonwhite and more likely to be reimbursed by Medicaid.¹⁸ The unique demographic makeup of hospital-based resident clinics raises questions about the preparedness and comfort of resident physicians in managing the nuances of health care delivery in these settings.¹⁰

Providing equitable care to marginalized populations within the constraints of 15- to 30-minute visits can be challenging to physicians and trainees. Even clinicians with the best of intentions may be impeded by a lack of familiarity with the daily realities of impoverished living conditions, implicit prejudice against people living in poverty, and adapting recommendations to varying levels of health literacy among patients.^19,20 Contending with these daunting obstacles can be discouraging. Given how entrenched certain institutional barriers are, questioning them may seem an exercise in futility, yet history demonstrates that residents can and have been empowered to improve tangible outcomes for vulnerable populations. In reflecting on approaches of the general medical education system, The Josiah Macy Jr. Foundation President George E. Thibault, MD, observed that, “When appropriately trained, deployed and incented, [residents] can help achieve institutional goals to improve quality, safety and efficiency.”²¹

Start Small But Dream Big

Action begins with awareness. Medical school and teaching hospital curricula are increasingly integrating educational exercises regarding the social determinants of health and populations with unmet needs. Medical training presents an exclusive opportunity to gain exposure to and familiarity with patient populations that one might not otherwise encounter. Immersion programs provide invaluable experience in tailoring health care delivery to the needs of vulnerable communities. Although opportunities for international rotations abound, domestic rotations among underserved populations can be just as transformative, including correctional medicine, homeless clinics, the Indian Health Service, and rural communities.

Create Partnerships to Broaden Impact of Service

Affecting the largest and most visible organ, skin disease often presents a substantial concern for patients and can herald systemic disease. The nature of dermatologic disease engenders close collaboration between general practitioners and specialists. For example, while resident-run or safety-net clinics characteristically center on providing holistic care for patients through internal medicine or primary care, these overworked and understaffed clinics often are in need of evaluation by specialists for specific concerns. Some clinic models feature dermatology faculty who volunteer routinely (ie, every 2 weeks, every month) to examine all the clinic’s patients presenting with concerns pertinent to the specialty. Drawing on their respective areas of expertise, general practitioners and dermatologists therefore can collaborate to connect disadvantaged patients with the specialized care they need.

Challenges Present Opportunities for Innovation

Adhering to the social distancing requirements of the COVID-19 pandemic protocol has driven clinicians to utilize innovative approaches to patient care. The rural-urban misdistribution of the dermatologist workforce has long been established, with rural patients often experiencing lengthy wait times to see a specialist.⁹ Both synchronous and asynchronous teledermatology modalities provide an ideal platform for triaging patients with dermatologic concerns who otherwise have meager access to a dermatologist.

Final Thoughts

Residency training is a prime opportunity to gain exposure to the broad spectrum of disease within dermatology as well as the diverse range of affected patients. Drawing on the aforementioned strategies, residents can leverage this knowledge in the service of underserved patients.

The Diagnosis: Frontal Fibrosing Alopecia Overlapping With Lichen Planus Pigmentosus 

Microscopic examination revealed focal dermal pigmentation, papillary fibrosis, and epidermal atrophy. These clinical and histologic findings indicated a diagnosis of fully developed lichen planus pigmentosus (LPP) overlapping with frontal fibrosing alopecia (FFA). Other cases have demonstrated an association between LPP and FFA.^1,2  

Lichen planus pigmentosus is considered an uncommon variant of lichen planus, as it has similar histopathologic findings and occasional coexistence.^3,4 It is characterized by hyperpigmented macules primarily located in sun-exposed and flexural areas of the skin. First described in India,⁵ this disease has a predilection for darker skin (Fitzpatrick skin types III-V),^6,7 and it has been reported in other racial and ethnic groups including Latin Americans, Middle Eastern populations, Japanese, and Koreans.^4,8 Typically, lesions initially appear as ill-defined, blue-grey, round to oval macules that coalesce into hyperpigmented patches. Involvement most commonly begins at the forehead and temples, which are affected in nearly all patients. Infrequently, LPP can be generalized or affect the oral mucosa; involvement of the palms, soles, and nails does not occur. Patients may be asymptomatic, but some experience mild pruritus and burning. The disease course is chronic and insidious, with new lesions appearing over time and old lesions progressively darkening and expanding.^6,7,9  

Although the pathogenesis of LPP is unknown, several exposures have been implicated, such as amla oil, mustard oil, henna, hair dye, and environmental pollutants.⁷ Because lesions characteristically occur in sun-exposed areas, UV light also may be involved. In addition, studies have suggested that LPP is associated with endocrinopathies such as diabetes mellitus and dyslipidemias, as in our patient, as well as autoimmune conditions such as vitiligo and systemic lupus erythematosus.^10,11  

Histopathologic findings are characterized by vacuolar degeneration of the basal layer in the epidermis as well as perivascular lymphohistiocytic infiltration and the presence of melanophages in the dermis.^3,9 Lichen planus pigmentosus is difficult to treat, as no consistently effective modality has been established. Topical tacrolimus, topical corticosteroids, oral retinoids, lasers, and sun protection have been implemented with underwhelming results.¹² 

Frontal fibrosing alopecia is a variant of lichen planopilaris that predominantly affects postmenopausal women and presents with frontotemporal hair loss in a bandlike distribution.^5,13 Both terminal and vellus hairs are affected. Involvement of multiple hair-bearing sites of the skin have been reported, including the entire scalp, eyebrows, and eyelashes. Affected areas may display hypopigmentation and be accompanied by pruritus and trichodynia.^14,15 The pathogenesis currently is under investigation, with studies demonstrating autoimmune, genetic, and possibly even endocrine predispositions.^16-18 Biopsies of lesions are indistinguishable from lichen planopilaris, which shows follicular lymphocytic infiltration, perifollicular fibrosis, interface dermatitis of the follicular infundibulum and isthmus, and vertical fibrous tracks.⁵ Patients with FFA have demonstrated variable responses to treatments, with one study showing improvement with oral finasteride or dutasteride.¹⁴ Topical and intralesional corticosteroids have yielded suboptimal effects. Other modalities include hydroxychloroquine and mycophenolate mofetil.^15,19 

Co-occurrence of LPP and FFA primarily is seen in postmenopausal women with darker skin,^14,15 as in our patient, though premenopausal cases have been reported. Lichen planus pigmentosus may serve as a harbinger in most patients.^1,2 In a similar fashion, our patient presented with hyperpigmented macular lesions prior to the onset of frontotemporal hair loss.  

Our patient was started on finasteride 2.5 mg daily, minoxidil foam 5%, clobetasol solution 0.05%, triamcinolone ointment 0.1%, and hydrocortisone ointment 2.5%. She was instructed to commence treatment and follow up in 6 months. 

The differential diagnosis includes dermatologic conditions that mimic both LPP and FFA. Postinflammatory hyperpigmentation and fixed drug reaction were unlikely based on the patient's history. The lesions of ashy dermatosis are characteristically gray erythematous macules on the trunk and limbs. Riehl melanosis is a rare pigmented contact dermatitis that is associated with a history of repeated contact with sensitizing allergens. Although Hori nevus is characterized by small, blue-gray or brown macules on the face, lesions predominantly occur on the bony prominences of the cheeks. Melasma also presents with dark to gray macules that affect the face and less commonly the neck, as in our patient.² 

Early discoid lupus erythematosus presents with round erythematous plaques with overlying scale extending into the hair follicles. In pseudopalade of Brocq, an idiopathic cicatricial alopecia, lesions typically are flesh colored. Biopsy also shows epidermal atrophy with additional dermal sclerosis and fibrosis. Folliculitis decalvans is a scarring form of alopecia associated with erythema and pustules, findings that were not present in our patient. Keratosis follicularis spinulosa decalvans is a rare, X-linked inherited ichthyosis manifesting as scarring alopecia with follicular depressions and papules on the scalp in younger males. Photophobia and other manifestations may be present. Alopecia mucinosa is a nonscarring alopecia with grouped follicular erythematous patches or plaques. Mucin sometimes can be squeezed from affected areas, and histopathologic examination shows mucin accumulation.⁴ 

The Diagnosis: Frontal Fibrosing Alopecia Overlapping With Lichen Planus Pigmentosus 

Microscopic examination revealed focal dermal pigmentation, papillary fibrosis, and epidermal atrophy. These clinical and histologic findings indicated a diagnosis of fully developed lichen planus pigmentosus (LPP) overlapping with frontal fibrosing alopecia (FFA). Other cases have demonstrated an association between LPP and FFA.^1,2  

Lichen planus pigmentosus is considered an uncommon variant of lichen planus, as it has similar histopathologic findings and occasional coexistence.^3,4 It is characterized by hyperpigmented macules primarily located in sun-exposed and flexural areas of the skin. First described in India,⁵ this disease has a predilection for darker skin (Fitzpatrick skin types III-V),^6,7 and it has been reported in other racial and ethnic groups including Latin Americans, Middle Eastern populations, Japanese, and Koreans.^4,8 Typically, lesions initially appear as ill-defined, blue-grey, round to oval macules that coalesce into hyperpigmented patches. Involvement most commonly begins at the forehead and temples, which are affected in nearly all patients. Infrequently, LPP can be generalized or affect the oral mucosa; involvement of the palms, soles, and nails does not occur. Patients may be asymptomatic, but some experience mild pruritus and burning. The disease course is chronic and insidious, with new lesions appearing over time and old lesions progressively darkening and expanding.^6,7,9  

Although the pathogenesis of LPP is unknown, several exposures have been implicated, such as amla oil, mustard oil, henna, hair dye, and environmental pollutants.⁷ Because lesions characteristically occur in sun-exposed areas, UV light also may be involved. In addition, studies have suggested that LPP is associated with endocrinopathies such as diabetes mellitus and dyslipidemias, as in our patient, as well as autoimmune conditions such as vitiligo and systemic lupus erythematosus.^10,11  

Histopathologic findings are characterized by vacuolar degeneration of the basal layer in the epidermis as well as perivascular lymphohistiocytic infiltration and the presence of melanophages in the dermis.^3,9 Lichen planus pigmentosus is difficult to treat, as no consistently effective modality has been established. Topical tacrolimus, topical corticosteroids, oral retinoids, lasers, and sun protection have been implemented with underwhelming results.¹² 

Frontal fibrosing alopecia is a variant of lichen planopilaris that predominantly affects postmenopausal women and presents with frontotemporal hair loss in a bandlike distribution.^5,13 Both terminal and vellus hairs are affected. Involvement of multiple hair-bearing sites of the skin have been reported, including the entire scalp, eyebrows, and eyelashes. Affected areas may display hypopigmentation and be accompanied by pruritus and trichodynia.^14,15 The pathogenesis currently is under investigation, with studies demonstrating autoimmune, genetic, and possibly even endocrine predispositions.^16-18 Biopsies of lesions are indistinguishable from lichen planopilaris, which shows follicular lymphocytic infiltration, perifollicular fibrosis, interface dermatitis of the follicular infundibulum and isthmus, and vertical fibrous tracks.⁵ Patients with FFA have demonstrated variable responses to treatments, with one study showing improvement with oral finasteride or dutasteride.¹⁴ Topical and intralesional corticosteroids have yielded suboptimal effects. Other modalities include hydroxychloroquine and mycophenolate mofetil.^15,19 

Co-occurrence of LPP and FFA primarily is seen in postmenopausal women with darker skin,^14,15 as in our patient, though premenopausal cases have been reported. Lichen planus pigmentosus may serve as a harbinger in most patients.^1,2 In a similar fashion, our patient presented with hyperpigmented macular lesions prior to the onset of frontotemporal hair loss.  

Our patient was started on finasteride 2.5 mg daily, minoxidil foam 5%, clobetasol solution 0.05%, triamcinolone ointment 0.1%, and hydrocortisone ointment 2.5%. She was instructed to commence treatment and follow up in 6 months. 

The differential diagnosis includes dermatologic conditions that mimic both LPP and FFA. Postinflammatory hyperpigmentation and fixed drug reaction were unlikely based on the patient's history. The lesions of ashy dermatosis are characteristically gray erythematous macules on the trunk and limbs. Riehl melanosis is a rare pigmented contact dermatitis that is associated with a history of repeated contact with sensitizing allergens. Although Hori nevus is characterized by small, blue-gray or brown macules on the face, lesions predominantly occur on the bony prominences of the cheeks. Melasma also presents with dark to gray macules that affect the face and less commonly the neck, as in our patient.² 

Early discoid lupus erythematosus presents with round erythematous plaques with overlying scale extending into the hair follicles. In pseudopalade of Brocq, an idiopathic cicatricial alopecia, lesions typically are flesh colored. Biopsy also shows epidermal atrophy with additional dermal sclerosis and fibrosis. Folliculitis decalvans is a scarring form of alopecia associated with erythema and pustules, findings that were not present in our patient. Keratosis follicularis spinulosa decalvans is a rare, X-linked inherited ichthyosis manifesting as scarring alopecia with follicular depressions and papules on the scalp in younger males. Photophobia and other manifestations may be present. Alopecia mucinosa is a nonscarring alopecia with grouped follicular erythematous patches or plaques. Mucin sometimes can be squeezed from affected areas, and histopathologic examination shows mucin accumulation.⁴ 

The Diagnosis: Frontal Fibrosing Alopecia Overlapping With Lichen Planus Pigmentosus 

Microscopic examination revealed focal dermal pigmentation, papillary fibrosis, and epidermal atrophy. These clinical and histologic findings indicated a diagnosis of fully developed lichen planus pigmentosus (LPP) overlapping with frontal fibrosing alopecia (FFA). Other cases have demonstrated an association between LPP and FFA.^1,2  

Lichen planus pigmentosus is considered an uncommon variant of lichen planus, as it has similar histopathologic findings and occasional coexistence.^3,4 It is characterized by hyperpigmented macules primarily located in sun-exposed and flexural areas of the skin. First described in India,⁵ this disease has a predilection for darker skin (Fitzpatrick skin types III-V),^6,7 and it has been reported in other racial and ethnic groups including Latin Americans, Middle Eastern populations, Japanese, and Koreans.^4,8 Typically, lesions initially appear as ill-defined, blue-grey, round to oval macules that coalesce into hyperpigmented patches. Involvement most commonly begins at the forehead and temples, which are affected in nearly all patients. Infrequently, LPP can be generalized or affect the oral mucosa; involvement of the palms, soles, and nails does not occur. Patients may be asymptomatic, but some experience mild pruritus and burning. The disease course is chronic and insidious, with new lesions appearing over time and old lesions progressively darkening and expanding.^6,7,9  

Although the pathogenesis of LPP is unknown, several exposures have been implicated, such as amla oil, mustard oil, henna, hair dye, and environmental pollutants.⁷ Because lesions characteristically occur in sun-exposed areas, UV light also may be involved. In addition, studies have suggested that LPP is associated with endocrinopathies such as diabetes mellitus and dyslipidemias, as in our patient, as well as autoimmune conditions such as vitiligo and systemic lupus erythematosus.^10,11  

Histopathologic findings are characterized by vacuolar degeneration of the basal layer in the epidermis as well as perivascular lymphohistiocytic infiltration and the presence of melanophages in the dermis.^3,9 Lichen planus pigmentosus is difficult to treat, as no consistently effective modality has been established. Topical tacrolimus, topical corticosteroids, oral retinoids, lasers, and sun protection have been implemented with underwhelming results.¹² 

Frontal fibrosing alopecia is a variant of lichen planopilaris that predominantly affects postmenopausal women and presents with frontotemporal hair loss in a bandlike distribution.^5,13 Both terminal and vellus hairs are affected. Involvement of multiple hair-bearing sites of the skin have been reported, including the entire scalp, eyebrows, and eyelashes. Affected areas may display hypopigmentation and be accompanied by pruritus and trichodynia.^14,15 The pathogenesis currently is under investigation, with studies demonstrating autoimmune, genetic, and possibly even endocrine predispositions.^16-18 Biopsies of lesions are indistinguishable from lichen planopilaris, which shows follicular lymphocytic infiltration, perifollicular fibrosis, interface dermatitis of the follicular infundibulum and isthmus, and vertical fibrous tracks.⁵ Patients with FFA have demonstrated variable responses to treatments, with one study showing improvement with oral finasteride or dutasteride.¹⁴ Topical and intralesional corticosteroids have yielded suboptimal effects. Other modalities include hydroxychloroquine and mycophenolate mofetil.^15,19 

Co-occurrence of LPP and FFA primarily is seen in postmenopausal women with darker skin,^14,15 as in our patient, though premenopausal cases have been reported. Lichen planus pigmentosus may serve as a harbinger in most patients.^1,2 In a similar fashion, our patient presented with hyperpigmented macular lesions prior to the onset of frontotemporal hair loss.  

Our patient was started on finasteride 2.5 mg daily, minoxidil foam 5%, clobetasol solution 0.05%, triamcinolone ointment 0.1%, and hydrocortisone ointment 2.5%. She was instructed to commence treatment and follow up in 6 months. 

The differential diagnosis includes dermatologic conditions that mimic both LPP and FFA. Postinflammatory hyperpigmentation and fixed drug reaction were unlikely based on the patient's history. The lesions of ashy dermatosis are characteristically gray erythematous macules on the trunk and limbs. Riehl melanosis is a rare pigmented contact dermatitis that is associated with a history of repeated contact with sensitizing allergens. Although Hori nevus is characterized by small, blue-gray or brown macules on the face, lesions predominantly occur on the bony prominences of the cheeks. Melasma also presents with dark to gray macules that affect the face and less commonly the neck, as in our patient.² 

Early discoid lupus erythematosus presents with round erythematous plaques with overlying scale extending into the hair follicles. In pseudopalade of Brocq, an idiopathic cicatricial alopecia, lesions typically are flesh colored. Biopsy also shows epidermal atrophy with additional dermal sclerosis and fibrosis. Folliculitis decalvans is a scarring form of alopecia associated with erythema and pustules, findings that were not present in our patient. Keratosis follicularis spinulosa decalvans is a rare, X-linked inherited ichthyosis manifesting as scarring alopecia with follicular depressions and papules on the scalp in younger males. Photophobia and other manifestations may be present. Alopecia mucinosa is a nonscarring alopecia with grouped follicular erythematous patches or plaques. Mucin sometimes can be squeezed from affected areas, and histopathologic examination shows mucin accumulation.⁴ 

The Diagnosis: Sweet Syndrome 

Sweet syndrome, alternatively known as acute febrile neutrophilic dermatosis, typically presents with variably tender, erythematous papules, plaques, or nodules in middle-aged adults.¹ Systemic symptoms such as fever, fatigue, and arthralgia often accompany these cutaneous findings.^1,2 Although the pathophysiology has not been fully elucidated, this syndrome frequently is associated with infections, especially upper respiratory illnesses; medications; and malignancies. Among cases of malignancy-associated Sweet syndrome, hematologic malignancies, particularly acute myeloid leukemia and myelodysplastic syndrome, are more common than solid organ malignancies.^1,2 Sweet syndrome may precede the associated malignancy by several months; thus, patients without an identifiable trigger for Sweet syndrome should be closely followed.² Treatment with systemic steroids typically is effective.^1,3 Typical histologic features include papillary dermal edema and a brisk neutrophilic infiltrate in the superficial to mid dermis (quiz image).⁴ Overlying epidermal spongiosis with or without vesiculation also can be seen.⁴ Leukocytoclasia and endothelial swelling without fibrinoid necrosis are typical, though full-blown leukocytoclastic vasculitis can be seen.^3,4 A histiocytoid variant also has been described in which the dermal infiltrate is composed of mononuclear cells reminiscent of histiocytes that are thought to be immature cells of myeloid origin. This variant histologically can simulate leukemia cutis.⁵  

Perniosis, also known as chilblains, typically presents with red to violaceous macules or papules on acral sites, particularly the distal fingers and toes.^6,7 It tends to affect young women more frequently than other demographic groups. Although the pathophysiology is not fully understood, perniosis is thought to represent an abnormal inflammatory response to cold environmental conditions. It can occur as an idiopathic disorder or in association with various systemic illnesses including lupus erythematosus.^6,7 The typical histologic findings include papillary dermal edema and a lymphocytic infiltrate in the superficial to deep dermis, often with perivascular and perieccrine accentuation (Figure 1).^3,6 Other less common microscopic findings include sparse keratinocyte necrosis, basal layer vacuolar change, swelling of endothelial cells, and lymphocytic vasculitis.⁶ The lesions typically resolve spontaneously within a few weeks, but in some cases they may be chronic.³ 

Polymorphous light eruption, a common photodermatosis induced by UV light exposure, typically presents in adolescence or early adulthood with a female predominance. Patients usually develop this pruritic rash on sun-exposed skin other than the face and dorsal aspects of the hands in the spring or early summer upon increased sun exposure after the winter season.^3,8 Consistent sunlight exposure throughout the summer months results in decreased flares. Various cutaneous morphologies including papules, vesicles, and plaques can be seen.^3,8 Histologic findings include papillary dermal edema and a perivascular lymphocytic infiltrate in the superficial to deep dermis (Figure 2).⁴  

Tinea corporis, a superficial cutaneous dermatophyte infection, typically presents as annular scaly plaques with central clearing. Vesicles and pustules also can be seen.³ The diagnosis can be confirmed via fungal culture, identification of hyphae on microscopic examination of skin scrapings using potassium hydroxide, or cutaneous biopsy. Histologic clues to diagnosis include a "compact stratum corneum (either uniform or forming a layer beneath a basket weave stratum corneum), parakeratosis, mild spongiosis, and neutrophils in the stratum corneum" (Figure 3).⁹ Papillary dermal edema also may be present, though this finding less commonly is reported.^9,10 Because fungal hyphae can be difficult to identify on hematoxylin and eosin-stained slides, special stains such as periodic acid-Schiff or Grocott-Gomori methenamine-silver may be helpful.⁹ These infections are managed with topical or oral antifungal medications.  

Wells syndrome, also known as eosinophilic cellulitis, presents with an acute eruption that can clinically resemble bacterial cellulitis.³ It has been described in children and adults with various clinical morphologies including plaques, bullae, papulovesicles, and papulonodules. Peripheral eosinophilia may be present.¹¹ The clinical lesions usually resolve spontaneously in a few weeks to months, but recurrences are typical.^3,11 Histologic findings include papillary dermal edema with or without subepidermal bulla formation and epidermal spongiosis as well as a mixed inflammatory infiltrate with a predominance of eosinophils and flame figures (Figure 4).⁴ Flame figures are collagen fibers coated with major basic protein and other constituents of degranulated eosinophils.³ Although flame figures often are present in Wells syndrome, they are not specific to this condition.^3,4 Some consider Wells syndrome an exaggerated reaction pattern rather than a specific entity.³ 

The Diagnosis: Sweet Syndrome 

Sweet syndrome, alternatively known as acute febrile neutrophilic dermatosis, typically presents with variably tender, erythematous papules, plaques, or nodules in middle-aged adults.¹ Systemic symptoms such as fever, fatigue, and arthralgia often accompany these cutaneous findings.^1,2 Although the pathophysiology has not been fully elucidated, this syndrome frequently is associated with infections, especially upper respiratory illnesses; medications; and malignancies. Among cases of malignancy-associated Sweet syndrome, hematologic malignancies, particularly acute myeloid leukemia and myelodysplastic syndrome, are more common than solid organ malignancies.^1,2 Sweet syndrome may precede the associated malignancy by several months; thus, patients without an identifiable trigger for Sweet syndrome should be closely followed.² Treatment with systemic steroids typically is effective.^1,3 Typical histologic features include papillary dermal edema and a brisk neutrophilic infiltrate in the superficial to mid dermis (quiz image).⁴ Overlying epidermal spongiosis with or without vesiculation also can be seen.⁴ Leukocytoclasia and endothelial swelling without fibrinoid necrosis are typical, though full-blown leukocytoclastic vasculitis can be seen.^3,4 A histiocytoid variant also has been described in which the dermal infiltrate is composed of mononuclear cells reminiscent of histiocytes that are thought to be immature cells of myeloid origin. This variant histologically can simulate leukemia cutis.⁵  

Perniosis, also known as chilblains, typically presents with red to violaceous macules or papules on acral sites, particularly the distal fingers and toes.^6,7 It tends to affect young women more frequently than other demographic groups. Although the pathophysiology is not fully understood, perniosis is thought to represent an abnormal inflammatory response to cold environmental conditions. It can occur as an idiopathic disorder or in association with various systemic illnesses including lupus erythematosus.^6,7 The typical histologic findings include papillary dermal edema and a lymphocytic infiltrate in the superficial to deep dermis, often with perivascular and perieccrine accentuation (Figure 1).^3,6 Other less common microscopic findings include sparse keratinocyte necrosis, basal layer vacuolar change, swelling of endothelial cells, and lymphocytic vasculitis.⁶ The lesions typically resolve spontaneously within a few weeks, but in some cases they may be chronic.³ 

Polymorphous light eruption, a common photodermatosis induced by UV light exposure, typically presents in adolescence or early adulthood with a female predominance. Patients usually develop this pruritic rash on sun-exposed skin other than the face and dorsal aspects of the hands in the spring or early summer upon increased sun exposure after the winter season.^3,8 Consistent sunlight exposure throughout the summer months results in decreased flares. Various cutaneous morphologies including papules, vesicles, and plaques can be seen.^3,8 Histologic findings include papillary dermal edema and a perivascular lymphocytic infiltrate in the superficial to deep dermis (Figure 2).⁴  

Tinea corporis, a superficial cutaneous dermatophyte infection, typically presents as annular scaly plaques with central clearing. Vesicles and pustules also can be seen.³ The diagnosis can be confirmed via fungal culture, identification of hyphae on microscopic examination of skin scrapings using potassium hydroxide, or cutaneous biopsy. Histologic clues to diagnosis include a "compact stratum corneum (either uniform or forming a layer beneath a basket weave stratum corneum), parakeratosis, mild spongiosis, and neutrophils in the stratum corneum" (Figure 3).⁹ Papillary dermal edema also may be present, though this finding less commonly is reported.^9,10 Because fungal hyphae can be difficult to identify on hematoxylin and eosin-stained slides, special stains such as periodic acid-Schiff or Grocott-Gomori methenamine-silver may be helpful.⁹ These infections are managed with topical or oral antifungal medications.  

Wells syndrome, also known as eosinophilic cellulitis, presents with an acute eruption that can clinically resemble bacterial cellulitis.³ It has been described in children and adults with various clinical morphologies including plaques, bullae, papulovesicles, and papulonodules. Peripheral eosinophilia may be present.¹¹ The clinical lesions usually resolve spontaneously in a few weeks to months, but recurrences are typical.^3,11 Histologic findings include papillary dermal edema with or without subepidermal bulla formation and epidermal spongiosis as well as a mixed inflammatory infiltrate with a predominance of eosinophils and flame figures (Figure 4).⁴ Flame figures are collagen fibers coated with major basic protein and other constituents of degranulated eosinophils.³ Although flame figures often are present in Wells syndrome, they are not specific to this condition.^3,4 Some consider Wells syndrome an exaggerated reaction pattern rather than a specific entity.³ 

The Diagnosis: Sweet Syndrome 

Sweet syndrome, alternatively known as acute febrile neutrophilic dermatosis, typically presents with variably tender, erythematous papules, plaques, or nodules in middle-aged adults.¹ Systemic symptoms such as fever, fatigue, and arthralgia often accompany these cutaneous findings.^1,2 Although the pathophysiology has not been fully elucidated, this syndrome frequently is associated with infections, especially upper respiratory illnesses; medications; and malignancies. Among cases of malignancy-associated Sweet syndrome, hematologic malignancies, particularly acute myeloid leukemia and myelodysplastic syndrome, are more common than solid organ malignancies.^1,2 Sweet syndrome may precede the associated malignancy by several months; thus, patients without an identifiable trigger for Sweet syndrome should be closely followed.² Treatment with systemic steroids typically is effective.^1,3 Typical histologic features include papillary dermal edema and a brisk neutrophilic infiltrate in the superficial to mid dermis (quiz image).⁴ Overlying epidermal spongiosis with or without vesiculation also can be seen.⁴ Leukocytoclasia and endothelial swelling without fibrinoid necrosis are typical, though full-blown leukocytoclastic vasculitis can be seen.^3,4 A histiocytoid variant also has been described in which the dermal infiltrate is composed of mononuclear cells reminiscent of histiocytes that are thought to be immature cells of myeloid origin. This variant histologically can simulate leukemia cutis.⁵  

Perniosis, also known as chilblains, typically presents with red to violaceous macules or papules on acral sites, particularly the distal fingers and toes.^6,7 It tends to affect young women more frequently than other demographic groups. Although the pathophysiology is not fully understood, perniosis is thought to represent an abnormal inflammatory response to cold environmental conditions. It can occur as an idiopathic disorder or in association with various systemic illnesses including lupus erythematosus.^6,7 The typical histologic findings include papillary dermal edema and a lymphocytic infiltrate in the superficial to deep dermis, often with perivascular and perieccrine accentuation (Figure 1).^3,6 Other less common microscopic findings include sparse keratinocyte necrosis, basal layer vacuolar change, swelling of endothelial cells, and lymphocytic vasculitis.⁶ The lesions typically resolve spontaneously within a few weeks, but in some cases they may be chronic.³ 

Polymorphous light eruption, a common photodermatosis induced by UV light exposure, typically presents in adolescence or early adulthood with a female predominance. Patients usually develop this pruritic rash on sun-exposed skin other than the face and dorsal aspects of the hands in the spring or early summer upon increased sun exposure after the winter season.^3,8 Consistent sunlight exposure throughout the summer months results in decreased flares. Various cutaneous morphologies including papules, vesicles, and plaques can be seen.^3,8 Histologic findings include papillary dermal edema and a perivascular lymphocytic infiltrate in the superficial to deep dermis (Figure 2).⁴  

Tinea corporis, a superficial cutaneous dermatophyte infection, typically presents as annular scaly plaques with central clearing. Vesicles and pustules also can be seen.³ The diagnosis can be confirmed via fungal culture, identification of hyphae on microscopic examination of skin scrapings using potassium hydroxide, or cutaneous biopsy. Histologic clues to diagnosis include a "compact stratum corneum (either uniform or forming a layer beneath a basket weave stratum corneum), parakeratosis, mild spongiosis, and neutrophils in the stratum corneum" (Figure 3).⁹ Papillary dermal edema also may be present, though this finding less commonly is reported.^9,10 Because fungal hyphae can be difficult to identify on hematoxylin and eosin-stained slides, special stains such as periodic acid-Schiff or Grocott-Gomori methenamine-silver may be helpful.⁹ These infections are managed with topical or oral antifungal medications.  

Wells syndrome, also known as eosinophilic cellulitis, presents with an acute eruption that can clinically resemble bacterial cellulitis.³ It has been described in children and adults with various clinical morphologies including plaques, bullae, papulovesicles, and papulonodules. Peripheral eosinophilia may be present.¹¹ The clinical lesions usually resolve spontaneously in a few weeks to months, but recurrences are typical.^3,11 Histologic findings include papillary dermal edema with or without subepidermal bulla formation and epidermal spongiosis as well as a mixed inflammatory infiltrate with a predominance of eosinophils and flame figures (Figure 4).⁴ Flame figures are collagen fibers coated with major basic protein and other constituents of degranulated eosinophils.³ Although flame figures often are present in Wells syndrome, they are not specific to this condition.^3,4 Some consider Wells syndrome an exaggerated reaction pattern rather than a specific entity.³ 

The Diagnosis: Bullous Amyloidosis 

A punch biopsy from the left temple showed deposits of amorphous eosinophilic material at the tips of dermal papillae and in the papillary dermis with hemorrhage present (Figure 1). A diagnosis of amyloidosis was confirmed on the biopsy of the skin bulla. The low κ/λ light chain ratio and M-spike with notably elevated free λ light chains in both serum and urine were consistent with a λ light chain primary systemic amyloidosis. The patient was seen by hematology and oncology. A bone marrow biopsy demonstrated that 15% to 20% of the clonal-cell population was λ light chain restricted. Eosinophilic extracellular deposits found in the adjacent soft tissue and bone marrow space were confirmed as amyloid with apple green birefringence under polarized light on Congo red stain and metachromatic staining with crystal violet. The patient ultimately was diagnosed with λ light chain multiple myeloma and primary systemic amyloidosis. 

Our patient was treated with a combination therapy of bortezomib, cyclophosphamide, and dexamethasone on 21-day cycles, with bortezomib on days 1, 4, 8, and 11. She had received 3 cycles of chemotherapy before developing diarrhea, hypotension, acute on chronic heart failure, and acute renal failure requiring hospitalization. She had several related complications due to amyloid light chain (AL) amyloidosis and subsequently died 16 days after her initial hospitalization from complications of methicillin-resistant Staphylococcus aureus bacteremia and septic shock. 

Amyloidosis is the pathologic deposition of abnormal protein in the extracellular space of any tissue. Various soluble precursor proteins can make up amyloid, and these proteins polymerize into insoluble fibrils that damage the surrounding parenchyma. The clinical presentation of amyloidosis varies depending on the affected tissue as well as the constituent protein. The amyloidoses are divided into localized cutaneous, primary systemic, and secondary systemic variants. The initial distinction in amyloidosis is determining whether it is skin limited or systemic. Localized cutaneous amyloidosis comprises 30% to 40% of all amyloidosis cases and is further divided into 3 main subtypes: macular, lichen, and nodular amyloidosis.¹ Macular and lichen amyloidosis are composed of keratin derivatives and typically are induced by patients when rubbing or scratching the skin. Histologically, macular and lichen amyloidosis are restricted to the superficial papillary dermis.¹ Nodular amyloidosis is composed of λ or κ light chain immunoglobulins, which are produced by cutaneous infiltrates of monoclonal plasma cells. Histologically, nodular amyloidosis is characterized by a diffuse dermal infiltrate of amorphous eosinophilic material.¹ Primary systemic amyloidosis is associated with an underlying plasma cell dyscrasia, and unlike secondary keratinocyte-derived amyloid, it can involve internal organs. Similar to nodular amyloidosis, primary systemic amyloidosis is composed of AL proteins, and it is histologically similar to nodular amyloidosis.¹ 

Primary systemic AL amyloidosis commonly affects individuals aged 50 to 60 years. Males and females are equally affected. Macroglossia and periorbital purpura are some of the pathognomonic presentations in AL amyloidosis. The major cause of death in these patients is cardiac and renal involvement. Renal involvement commonly presents as nephrotic syndrome, and cardiac involvement can present as a restrictive cardiomyopathy with dyspnea. Other symptoms include edema, hepatosplenomegaly, bleeding diathesis, and carpal tunnel syndrome.² An evaluation for AL amyloidosis should include a complete review of systems and physical examination with studies such as complete blood cell count, comprehensive metabolic panel, serum and urine protein electrophoresis and immunofixation, and electrocardiogram. 

Cutaneous involvement in AL amyloidosis most commonly includes yellowish waxy papules, nodules, and plaques but also can include purpura and petechiae.² Bullous amyloidosis, as seen in our patient, is a rare cutaneous presentation of AL amyloidosis that usually is negative for the Nikolsky sign (Figure 2). Bullae form due to weakness in amyloid-laden dermal connective tissue.³ Eighty-eight percent of cases of bullous amyloidosis have systemic involvement.¹ Some cases have reported a familial linkage, suggesting there might be a genetic component to the disease.⁴ A PubMed search of articles indexed for MEDLINE using the terms bullous amyloidosis, bullous, amyloidosis, and amyloid revealed fewer than 35 cases of bullous amyloidosis in the English-language literature.⁵ Bullae can be located intradermally or subepidermally and commonly are hemorrhagic but also can be translucent, tender, and tense. 

A study of electron microscopy in a patient with systemic bullous amyloidosis demonstrated amyloid and keratinocyte protrusions that perforated the dermis through the spaces in the lamina densa. The study concluded that the disintegration of the lamina densa and expansion of the intercellular spaces between keratinocytes were the causes of skin fragility as well as fluid exudation.⁵ Trauma or friction to the skin are local precipitating factors for blister formation in bullous amyloidosis.  

Bullae can become apparent at any stage of AL amyloidosis, but they generally increase in size and number over time and are most common in intertriginous areas. Bullous amyloid lesions, especially those located in intertriginous areas, can have secondary impetiginization.⁶ In many cases, patients who present with bullous amyloidosis ultimately will be diagnosed with multiple myeloma or another plasma cell dyscrasia. In AL amyloidosis, only 10% to 15% of cases meet criteria for multiple myeloma, whereas 80% or more patients have a monoclonal gammopathy of undetermined significance.⁷  

The prognosis of cutaneous amyloidosis depends on the extent of organ involvement and response to treatment. Treatment is aimed at eliminating clonal plasma cell populations to decrease the production of light chains, thereby decreasing protein burden and amyloid progression. Historically, treatment options included cytotoxic chemotherapy such as oral melphalan and dexamethasone, followed by hematopoietic stem cell transplant. More recent treatment options include bortezomib, thalidomide, pomalidomide, and lenalidomide.⁸ Our patient received a regimen of bortezomib, cyclophosphamide, and dexamethasone that is used for patients with extensive multiple myeloma.  

The differential diagnosis in our patient included bullous drug eruption, which should be considered if the bullae are reoccurring at the same location and in association with the administration of a culprit drug. Bullous pemphigoid is preceded by pruritus, and biopsy demonstrates subepidermal bullae with associated eosinophilic infiltrate. Epidermolysis bullosa acquisita can present with milia and a linear pattern along the basement membrane zone with direct immunofluorescence. Traumatic purpura usually present with the classic shape and hue of an ecchymosis, and the patient will have a history of trauma. 

Cutaneous involvement of amyloidosis can be an early clue to the diagnosis of plasma cell dyscrasia. Early diagnosis and treatment can portend a better prognosis and prevent progression to renal or cardiac disease. 

The Diagnosis: Bullous Amyloidosis 

A punch biopsy from the left temple showed deposits of amorphous eosinophilic material at the tips of dermal papillae and in the papillary dermis with hemorrhage present (Figure 1). A diagnosis of amyloidosis was confirmed on the biopsy of the skin bulla. The low κ/λ light chain ratio and M-spike with notably elevated free λ light chains in both serum and urine were consistent with a λ light chain primary systemic amyloidosis. The patient was seen by hematology and oncology. A bone marrow biopsy demonstrated that 15% to 20% of the clonal-cell population was λ light chain restricted. Eosinophilic extracellular deposits found in the adjacent soft tissue and bone marrow space were confirmed as amyloid with apple green birefringence under polarized light on Congo red stain and metachromatic staining with crystal violet. The patient ultimately was diagnosed with λ light chain multiple myeloma and primary systemic amyloidosis. 

Our patient was treated with a combination therapy of bortezomib, cyclophosphamide, and dexamethasone on 21-day cycles, with bortezomib on days 1, 4, 8, and 11. She had received 3 cycles of chemotherapy before developing diarrhea, hypotension, acute on chronic heart failure, and acute renal failure requiring hospitalization. She had several related complications due to amyloid light chain (AL) amyloidosis and subsequently died 16 days after her initial hospitalization from complications of methicillin-resistant Staphylococcus aureus bacteremia and septic shock. 

Amyloidosis is the pathologic deposition of abnormal protein in the extracellular space of any tissue. Various soluble precursor proteins can make up amyloid, and these proteins polymerize into insoluble fibrils that damage the surrounding parenchyma. The clinical presentation of amyloidosis varies depending on the affected tissue as well as the constituent protein. The amyloidoses are divided into localized cutaneous, primary systemic, and secondary systemic variants. The initial distinction in amyloidosis is determining whether it is skin limited or systemic. Localized cutaneous amyloidosis comprises 30% to 40% of all amyloidosis cases and is further divided into 3 main subtypes: macular, lichen, and nodular amyloidosis.¹ Macular and lichen amyloidosis are composed of keratin derivatives and typically are induced by patients when rubbing or scratching the skin. Histologically, macular and lichen amyloidosis are restricted to the superficial papillary dermis.¹ Nodular amyloidosis is composed of λ or κ light chain immunoglobulins, which are produced by cutaneous infiltrates of monoclonal plasma cells. Histologically, nodular amyloidosis is characterized by a diffuse dermal infiltrate of amorphous eosinophilic material.¹ Primary systemic amyloidosis is associated with an underlying plasma cell dyscrasia, and unlike secondary keratinocyte-derived amyloid, it can involve internal organs. Similar to nodular amyloidosis, primary systemic amyloidosis is composed of AL proteins, and it is histologically similar to nodular amyloidosis.¹ 

Primary systemic AL amyloidosis commonly affects individuals aged 50 to 60 years. Males and females are equally affected. Macroglossia and periorbital purpura are some of the pathognomonic presentations in AL amyloidosis. The major cause of death in these patients is cardiac and renal involvement. Renal involvement commonly presents as nephrotic syndrome, and cardiac involvement can present as a restrictive cardiomyopathy with dyspnea. Other symptoms include edema, hepatosplenomegaly, bleeding diathesis, and carpal tunnel syndrome.² An evaluation for AL amyloidosis should include a complete review of systems and physical examination with studies such as complete blood cell count, comprehensive metabolic panel, serum and urine protein electrophoresis and immunofixation, and electrocardiogram. 

Cutaneous involvement in AL amyloidosis most commonly includes yellowish waxy papules, nodules, and plaques but also can include purpura and petechiae.² Bullous amyloidosis, as seen in our patient, is a rare cutaneous presentation of AL amyloidosis that usually is negative for the Nikolsky sign (Figure 2). Bullae form due to weakness in amyloid-laden dermal connective tissue.³ Eighty-eight percent of cases of bullous amyloidosis have systemic involvement.¹ Some cases have reported a familial linkage, suggesting there might be a genetic component to the disease.⁴ A PubMed search of articles indexed for MEDLINE using the terms bullous amyloidosis, bullous, amyloidosis, and amyloid revealed fewer than 35 cases of bullous amyloidosis in the English-language literature.⁵ Bullae can be located intradermally or subepidermally and commonly are hemorrhagic but also can be translucent, tender, and tense. 

A study of electron microscopy in a patient with systemic bullous amyloidosis demonstrated amyloid and keratinocyte protrusions that perforated the dermis through the spaces in the lamina densa. The study concluded that the disintegration of the lamina densa and expansion of the intercellular spaces between keratinocytes were the causes of skin fragility as well as fluid exudation.⁵ Trauma or friction to the skin are local precipitating factors for blister formation in bullous amyloidosis.  

Bullae can become apparent at any stage of AL amyloidosis, but they generally increase in size and number over time and are most common in intertriginous areas. Bullous amyloid lesions, especially those located in intertriginous areas, can have secondary impetiginization.⁶ In many cases, patients who present with bullous amyloidosis ultimately will be diagnosed with multiple myeloma or another plasma cell dyscrasia. In AL amyloidosis, only 10% to 15% of cases meet criteria for multiple myeloma, whereas 80% or more patients have a monoclonal gammopathy of undetermined significance.⁷  

The prognosis of cutaneous amyloidosis depends on the extent of organ involvement and response to treatment. Treatment is aimed at eliminating clonal plasma cell populations to decrease the production of light chains, thereby decreasing protein burden and amyloid progression. Historically, treatment options included cytotoxic chemotherapy such as oral melphalan and dexamethasone, followed by hematopoietic stem cell transplant. More recent treatment options include bortezomib, thalidomide, pomalidomide, and lenalidomide.⁸ Our patient received a regimen of bortezomib, cyclophosphamide, and dexamethasone that is used for patients with extensive multiple myeloma.  

The differential diagnosis in our patient included bullous drug eruption, which should be considered if the bullae are reoccurring at the same location and in association with the administration of a culprit drug. Bullous pemphigoid is preceded by pruritus, and biopsy demonstrates subepidermal bullae with associated eosinophilic infiltrate. Epidermolysis bullosa acquisita can present with milia and a linear pattern along the basement membrane zone with direct immunofluorescence. Traumatic purpura usually present with the classic shape and hue of an ecchymosis, and the patient will have a history of trauma. 

Cutaneous involvement of amyloidosis can be an early clue to the diagnosis of plasma cell dyscrasia. Early diagnosis and treatment can portend a better prognosis and prevent progression to renal or cardiac disease. 

The Diagnosis: Bullous Amyloidosis 

A punch biopsy from the left temple showed deposits of amorphous eosinophilic material at the tips of dermal papillae and in the papillary dermis with hemorrhage present (Figure 1). A diagnosis of amyloidosis was confirmed on the biopsy of the skin bulla. The low κ/λ light chain ratio and M-spike with notably elevated free λ light chains in both serum and urine were consistent with a λ light chain primary systemic amyloidosis. The patient was seen by hematology and oncology. A bone marrow biopsy demonstrated that 15% to 20% of the clonal-cell population was λ light chain restricted. Eosinophilic extracellular deposits found in the adjacent soft tissue and bone marrow space were confirmed as amyloid with apple green birefringence under polarized light on Congo red stain and metachromatic staining with crystal violet. The patient ultimately was diagnosed with λ light chain multiple myeloma and primary systemic amyloidosis. 

Our patient was treated with a combination therapy of bortezomib, cyclophosphamide, and dexamethasone on 21-day cycles, with bortezomib on days 1, 4, 8, and 11. She had received 3 cycles of chemotherapy before developing diarrhea, hypotension, acute on chronic heart failure, and acute renal failure requiring hospitalization. She had several related complications due to amyloid light chain (AL) amyloidosis and subsequently died 16 days after her initial hospitalization from complications of methicillin-resistant Staphylococcus aureus bacteremia and septic shock. 

Amyloidosis is the pathologic deposition of abnormal protein in the extracellular space of any tissue. Various soluble precursor proteins can make up amyloid, and these proteins polymerize into insoluble fibrils that damage the surrounding parenchyma. The clinical presentation of amyloidosis varies depending on the affected tissue as well as the constituent protein. The amyloidoses are divided into localized cutaneous, primary systemic, and secondary systemic variants. The initial distinction in amyloidosis is determining whether it is skin limited or systemic. Localized cutaneous amyloidosis comprises 30% to 40% of all amyloidosis cases and is further divided into 3 main subtypes: macular, lichen, and nodular amyloidosis.¹ Macular and lichen amyloidosis are composed of keratin derivatives and typically are induced by patients when rubbing or scratching the skin. Histologically, macular and lichen amyloidosis are restricted to the superficial papillary dermis.¹ Nodular amyloidosis is composed of λ or κ light chain immunoglobulins, which are produced by cutaneous infiltrates of monoclonal plasma cells. Histologically, nodular amyloidosis is characterized by a diffuse dermal infiltrate of amorphous eosinophilic material.¹ Primary systemic amyloidosis is associated with an underlying plasma cell dyscrasia, and unlike secondary keratinocyte-derived amyloid, it can involve internal organs. Similar to nodular amyloidosis, primary systemic amyloidosis is composed of AL proteins, and it is histologically similar to nodular amyloidosis.¹ 

Primary systemic AL amyloidosis commonly affects individuals aged 50 to 60 years. Males and females are equally affected. Macroglossia and periorbital purpura are some of the pathognomonic presentations in AL amyloidosis. The major cause of death in these patients is cardiac and renal involvement. Renal involvement commonly presents as nephrotic syndrome, and cardiac involvement can present as a restrictive cardiomyopathy with dyspnea. Other symptoms include edema, hepatosplenomegaly, bleeding diathesis, and carpal tunnel syndrome.² An evaluation for AL amyloidosis should include a complete review of systems and physical examination with studies such as complete blood cell count, comprehensive metabolic panel, serum and urine protein electrophoresis and immunofixation, and electrocardiogram. 

Cutaneous involvement in AL amyloidosis most commonly includes yellowish waxy papules, nodules, and plaques but also can include purpura and petechiae.² Bullous amyloidosis, as seen in our patient, is a rare cutaneous presentation of AL amyloidosis that usually is negative for the Nikolsky sign (Figure 2). Bullae form due to weakness in amyloid-laden dermal connective tissue.³ Eighty-eight percent of cases of bullous amyloidosis have systemic involvement.¹ Some cases have reported a familial linkage, suggesting there might be a genetic component to the disease.⁴ A PubMed search of articles indexed for MEDLINE using the terms bullous amyloidosis, bullous, amyloidosis, and amyloid revealed fewer than 35 cases of bullous amyloidosis in the English-language literature.⁵ Bullae can be located intradermally or subepidermally and commonly are hemorrhagic but also can be translucent, tender, and tense. 

A study of electron microscopy in a patient with systemic bullous amyloidosis demonstrated amyloid and keratinocyte protrusions that perforated the dermis through the spaces in the lamina densa. The study concluded that the disintegration of the lamina densa and expansion of the intercellular spaces between keratinocytes were the causes of skin fragility as well as fluid exudation.⁵ Trauma or friction to the skin are local precipitating factors for blister formation in bullous amyloidosis.  

Bullae can become apparent at any stage of AL amyloidosis, but they generally increase in size and number over time and are most common in intertriginous areas. Bullous amyloid lesions, especially those located in intertriginous areas, can have secondary impetiginization.⁶ In many cases, patients who present with bullous amyloidosis ultimately will be diagnosed with multiple myeloma or another plasma cell dyscrasia. In AL amyloidosis, only 10% to 15% of cases meet criteria for multiple myeloma, whereas 80% or more patients have a monoclonal gammopathy of undetermined significance.⁷  

The prognosis of cutaneous amyloidosis depends on the extent of organ involvement and response to treatment. Treatment is aimed at eliminating clonal plasma cell populations to decrease the production of light chains, thereby decreasing protein burden and amyloid progression. Historically, treatment options included cytotoxic chemotherapy such as oral melphalan and dexamethasone, followed by hematopoietic stem cell transplant. More recent treatment options include bortezomib, thalidomide, pomalidomide, and lenalidomide.⁸ Our patient received a regimen of bortezomib, cyclophosphamide, and dexamethasone that is used for patients with extensive multiple myeloma.  

The differential diagnosis in our patient included bullous drug eruption, which should be considered if the bullae are reoccurring at the same location and in association with the administration of a culprit drug. Bullous pemphigoid is preceded by pruritus, and biopsy demonstrates subepidermal bullae with associated eosinophilic infiltrate. Epidermolysis bullosa acquisita can present with milia and a linear pattern along the basement membrane zone with direct immunofluorescence. Traumatic purpura usually present with the classic shape and hue of an ecchymosis, and the patient will have a history of trauma. 

Cutaneous involvement of amyloidosis can be an early clue to the diagnosis of plasma cell dyscrasia. Early diagnosis and treatment can portend a better prognosis and prevent progression to renal or cardiac disease. 

Practice Gap

Multiple keratoacanthomas (KAs) of the legs often are a challenge to treat, especially when these lesions appear within a field of prurigo nodules. Multiple KAs associated with prurigo nodularis is a rarer finding; more often, the condition is reported on the lower limbs of elderly women with actinically damaged skin.^1,2 At times, it can be difficult to distinguish between KA and prurigo nodularis in these patients, who often report notable pruritus and might have associated eczematous dermatitis.²

Keratoacanthomas often are treated with aggressive modalities, such as Mohs micrographic surgery, excision, and electrodesiccation and curettage. Some patients are hesitant to undergo surgical treatment, however, preferring a less invasive approach. Trauma from these aggressive modalities also can be associated with recurrence of existing lesions or development of new KAs, possibly related to stimulation of a local inflammatory response and upregulation of helper T cells.^2-4

Acitretin and other systemic retinoids often are considered first-line therapy for multiple KAs. Cyclosporine has been added as adjunctive treatment in cases associated with prurigo nodularis or eczematous dermatitis^1,2; however, these treatments have a high rate of discontinuation because of adverse effects, including transaminitis, xerostomia, alopecia (acitretin), and renal toxicity (cyclosporine).²

Another treatment option for patients with coexisting KA and prurigo nodularis is intralesional corticosteroids, often administered in combination with systemic retinoids.³ Topical 5-fluorouracil (5-FU) has been used successfully for KA, but topical treatment options are limited if 5-FU fails. Topical imiquimod and cryotherapy are thought to be of little benefit, and the appearance of new KA within imiquimod and cryotherapy treatment fields has been reported.^1,2 Topical corticosteroids have been used as an adjuvant therapy for multiple KAs associated with prurigo nodularis; however, a PubMed search of articles indexed for MEDLINE using the terms keratoacanthoma and steroid and keratoacanthoma and prurigo nodularis yielded no published reports of successful use of topical corticosteroids as monotherapy.²

The Technique

For patients who want to continue topical treatment of coexisting KA and prurigo nodularis after topical 5-FU fails, we have found success applying a high-potency topical corticosteroid to affected areas under occlusion nightly for 6 to 8 weeks. This treatment not only leads to resolution of KA but also simultaneously treats prurigo nodules that might be clinically difficult to distinguish from KA in some presentations. This regimen has been implemented in our practice with remarkable reduction of KA burden and relief of pruritus.

In a 68-year-old woman who was treated with this technique, multiple biopsies had shown KA (or well-differentiated squamous cell carcinoma that appeared clinically as KA) on the shin (Figure, A) arising amid many lesions consistent with prurigo nodules. Topical 5-FU had failed, but the patient did not want to be treated with a more invasive modality, such as excision or injection.

Practical Implications

Treatment of multiple KAs associated with prurigo nodularis can present a distinct challenge. For the subset of patients who want to pursue topical treatment, options reported in the literature are limited. We have found success treating multiple KAs and associated prurigo nodules with a high-potency topical corticosteroid under occlusion, with minimal or no adverse effects. We believe that a topical corticosteroid can be implemented easily in clinical practice before a more invasive surgical or intralesional modality is considered.

Practice Gap

Multiple keratoacanthomas (KAs) of the legs often are a challenge to treat, especially when these lesions appear within a field of prurigo nodules. Multiple KAs associated with prurigo nodularis is a rarer finding; more often, the condition is reported on the lower limbs of elderly women with actinically damaged skin.^1,2 At times, it can be difficult to distinguish between KA and prurigo nodularis in these patients, who often report notable pruritus and might have associated eczematous dermatitis.²

Keratoacanthomas often are treated with aggressive modalities, such as Mohs micrographic surgery, excision, and electrodesiccation and curettage. Some patients are hesitant to undergo surgical treatment, however, preferring a less invasive approach. Trauma from these aggressive modalities also can be associated with recurrence of existing lesions or development of new KAs, possibly related to stimulation of a local inflammatory response and upregulation of helper T cells.^2-4

Acitretin and other systemic retinoids often are considered first-line therapy for multiple KAs. Cyclosporine has been added as adjunctive treatment in cases associated with prurigo nodularis or eczematous dermatitis^1,2; however, these treatments have a high rate of discontinuation because of adverse effects, including transaminitis, xerostomia, alopecia (acitretin), and renal toxicity (cyclosporine).²

Another treatment option for patients with coexisting KA and prurigo nodularis is intralesional corticosteroids, often administered in combination with systemic retinoids.³ Topical 5-fluorouracil (5-FU) has been used successfully for KA, but topical treatment options are limited if 5-FU fails. Topical imiquimod and cryotherapy are thought to be of little benefit, and the appearance of new KA within imiquimod and cryotherapy treatment fields has been reported.^1,2 Topical corticosteroids have been used as an adjuvant therapy for multiple KAs associated with prurigo nodularis; however, a PubMed search of articles indexed for MEDLINE using the terms keratoacanthoma and steroid and keratoacanthoma and prurigo nodularis yielded no published reports of successful use of topical corticosteroids as monotherapy.²

The Technique

For patients who want to continue topical treatment of coexisting KA and prurigo nodularis after topical 5-FU fails, we have found success applying a high-potency topical corticosteroid to affected areas under occlusion nightly for 6 to 8 weeks. This treatment not only leads to resolution of KA but also simultaneously treats prurigo nodules that might be clinically difficult to distinguish from KA in some presentations. This regimen has been implemented in our practice with remarkable reduction of KA burden and relief of pruritus.

In a 68-year-old woman who was treated with this technique, multiple biopsies had shown KA (or well-differentiated squamous cell carcinoma that appeared clinically as KA) on the shin (Figure, A) arising amid many lesions consistent with prurigo nodules. Topical 5-FU had failed, but the patient did not want to be treated with a more invasive modality, such as excision or injection.

Practical Implications

Treatment of multiple KAs associated with prurigo nodularis can present a distinct challenge. For the subset of patients who want to pursue topical treatment, options reported in the literature are limited. We have found success treating multiple KAs and associated prurigo nodules with a high-potency topical corticosteroid under occlusion, with minimal or no adverse effects. We believe that a topical corticosteroid can be implemented easily in clinical practice before a more invasive surgical or intralesional modality is considered.

Practice Gap

Multiple keratoacanthomas (KAs) of the legs often are a challenge to treat, especially when these lesions appear within a field of prurigo nodules. Multiple KAs associated with prurigo nodularis is a rarer finding; more often, the condition is reported on the lower limbs of elderly women with actinically damaged skin.^1,2 At times, it can be difficult to distinguish between KA and prurigo nodularis in these patients, who often report notable pruritus and might have associated eczematous dermatitis.²

Keratoacanthomas often are treated with aggressive modalities, such as Mohs micrographic surgery, excision, and electrodesiccation and curettage. Some patients are hesitant to undergo surgical treatment, however, preferring a less invasive approach. Trauma from these aggressive modalities also can be associated with recurrence of existing lesions or development of new KAs, possibly related to stimulation of a local inflammatory response and upregulation of helper T cells.^2-4

Acitretin and other systemic retinoids often are considered first-line therapy for multiple KAs. Cyclosporine has been added as adjunctive treatment in cases associated with prurigo nodularis or eczematous dermatitis^1,2; however, these treatments have a high rate of discontinuation because of adverse effects, including transaminitis, xerostomia, alopecia (acitretin), and renal toxicity (cyclosporine).²

Another treatment option for patients with coexisting KA and prurigo nodularis is intralesional corticosteroids, often administered in combination with systemic retinoids.³ Topical 5-fluorouracil (5-FU) has been used successfully for KA, but topical treatment options are limited if 5-FU fails. Topical imiquimod and cryotherapy are thought to be of little benefit, and the appearance of new KA within imiquimod and cryotherapy treatment fields has been reported.^1,2 Topical corticosteroids have been used as an adjuvant therapy for multiple KAs associated with prurigo nodularis; however, a PubMed search of articles indexed for MEDLINE using the terms keratoacanthoma and steroid and keratoacanthoma and prurigo nodularis yielded no published reports of successful use of topical corticosteroids as monotherapy.²

The Technique

For patients who want to continue topical treatment of coexisting KA and prurigo nodularis after topical 5-FU fails, we have found success applying a high-potency topical corticosteroid to affected areas under occlusion nightly for 6 to 8 weeks. This treatment not only leads to resolution of KA but also simultaneously treats prurigo nodules that might be clinically difficult to distinguish from KA in some presentations. This regimen has been implemented in our practice with remarkable reduction of KA burden and relief of pruritus.

In a 68-year-old woman who was treated with this technique, multiple biopsies had shown KA (or well-differentiated squamous cell carcinoma that appeared clinically as KA) on the shin (Figure, A) arising amid many lesions consistent with prurigo nodules. Topical 5-FU had failed, but the patient did not want to be treated with a more invasive modality, such as excision or injection.

Practical Implications

Treatment of multiple KAs associated with prurigo nodularis can present a distinct challenge. For the subset of patients who want to pursue topical treatment, options reported in the literature are limited. We have found success treating multiple KAs and associated prurigo nodules with a high-potency topical corticosteroid under occlusion, with minimal or no adverse effects. We believe that a topical corticosteroid can be implemented easily in clinical practice before a more invasive surgical or intralesional modality is considered.

Darier disease (DD)(also known as dyskeratosis follicularis) is a rare, autosomal-dominant genodermatosis characterized by greasy, rough, keratotic papules; typical nail abnormalities; mucosal changes; and characteristic dyskeratotic acantholysis that is called corps ronds and grains on histopathologic analysis. Darier disease is caused by mutations of the ATP2A2 gene on chromosome 12q23-24.^1,2

Because of the autosomal-dominant pattern of inheritance in DD, if either parent is affected by DD, approximately 50% of their offspring will have the disorder. Therefore, couples need to be offered genetic counseling at a preconception visit or early in pregnancy. Although penetrance of DD is complete, spontaneous mutations are frequent and expressivity is variable¹; prenatal diagnosis, though available since the 1980s, is therefore unreliable in DD, given the considerable variation in phenotypic expressivity. Differing phenotypes underscore the importance of proper counseling by the treating dermatologist or other provider. Females with a mild or nearly undetectable phenotype can give birth to a child with severe disease.

Lack of clear understanding about the variable phenotypic expressivity of DD can cause considerable anger, anxiety, guilt, psychological trauma, and fear in parents, should their child later develop a severe phenotype. They may feel that they were not properly prepared for the outcome. The physician-parent or physician-patient relationship can be negatively impacted if ongoing counseling is inadequate.

Clinically, DD presents in early adolescence (age range, 6–20 years) in most patients, which means that the disease and female reproductive years are contemporaneous. However, gynecologic and obstetric issues and complications of DD rarely have been addressed.³ Oromucosal involvement in DD is reported in 13% to 50% of cases, yet vaginal and cervical mucosal involvement rarely has been described,^4,5 likely due to underreporting. Therefore, in this rare disease, it is important to address these aspects so that the patients are provided with appropriate management options.

Implications for Cervical Screening and Papanicolaou Tests

Cytopathologic findings of a Papanicolaou test taken from a patient with DD can lead to erroneous diagnosis of a low-grade squamous intraepithelial lesion due to cervical involvement by the disease process; therefore, correct interpretation of a smear may be inappropriate and erroneous. The cytopathologist needs to be informed of the patient’s diagnosis of DD in advance for appropriate reporting.^5,6

Obstetric Implications

Fertility is normal in DD patients, and pregnancy usually has a normal course; however, exacerbation and remission of disease have been reported. de la Rosa Carrillo⁷ reported a case of vegetating DD during pregnancy. He described it as an exacerbation with concurrent bacterial infection and bilateral external otitis.⁷ Spouge et al⁸ reported a case of a 58-year-old woman who was the mother of 4 DD patients. She experienced an exacerbation of DD during all 6 pregnancies but improved immediately postpartum.⁸ Espy et al⁹ evaluated 8 cases of women with DD and described spontaneous improvement of the disorder during pregnancy (1 case) or while taking an oral contraceptive (3 cases).

Prenatal Counseling

Women with DD should be encouraged to talk to their dermatologist, obstetrician, or other provider of prenatal care regarding plans for pregnancy, labor, and delivery, as these events might be affected by the disorder. During pregnancy, careful monitoring and self-care remain essential. Simple measures to reduce the impact of irritants on DD during pregnancy include keeping the skin cool, using a soothing moisturizer, applying photoprotection, and using sunscreen. Treatment with systemic retinoids must be avoided if pregnancy is planned.

Warty plaques and papules of DD can involve flexures (groin, vulva, and perineum), with resultant malodor and pruritus¹⁰ as well as the potential for (drug resistant) secondary infection (eg, Staphylococcus aureus, group B Streptococcus, viruses [eg, Kaposi varicelliform eruption]). Skin swabs should be taken for culture and susceptibility testing, and infection should be treated at the earliest sign.

Management Concerns During Pregnancy and Delivery

Because the benefits of treating DD might outweigh risk in certain cases, thorough discussion with the patient about options is recommended, including the following concerns:

• Because mucocutaneous elasticity of the birth canal, including the vulva, perineum, and groin, is essential for nontraumatic vaginal delivery, it might be necessary to schedule an elective cesarean delivery in DD patients in whom these regions are involved.¹¹

• In females with lower abdominal lesions, using a Pfannenstiel-Kerr incision for cesarean delivery might be problematic.¹¹

• A single case report has described successful anesthetic management of labor, delivery, and postpartum care in a DD patient.¹² Involvement of the skin of the back might preclude safe administration of regional anesthesia; however, because DD lesions are considered noninfectious, the authors operatively administered a subarachnoid block at the L3-L4 interspace through a lesion-free area. Postpartum, the patient was observed in the intensive care unit. She and the baby remained stable; she did not develop infectious complications, including a central nervous system infection.¹²

•Mucosal involvement is relatively rare in DD and has not been reported to compromise airway management.⁸

Postnatal Considerations

Breastfeeding might have to be stopped early or withheld altogether if there is widespread involvement of the skin of the breast or the nipple.¹¹ Darier disease has been associated with neuropsychiatric manifestations, including major depression (30%), suicide attempts (13%), suicidal thoughts (31%), cyclothymia, bipolar disorder (4%), and epilepsy (3%).^13,14 Therefore, patients should be screened for postpartum psychiatric manifestations at an early follow-up visit.

Final Thoughts

Although the etiology of DD is well known, the gynelogic and obstretric implications of this genodermatosis have rarely been described. This brief commentary is an attempt to provide the important information to a practicing dermatologist for appropriate management of female DD patients.

Darier disease (DD)(also known as dyskeratosis follicularis) is a rare, autosomal-dominant genodermatosis characterized by greasy, rough, keratotic papules; typical nail abnormalities; mucosal changes; and characteristic dyskeratotic acantholysis that is called corps ronds and grains on histopathologic analysis. Darier disease is caused by mutations of the ATP2A2 gene on chromosome 12q23-24.^1,2

Because of the autosomal-dominant pattern of inheritance in DD, if either parent is affected by DD, approximately 50% of their offspring will have the disorder. Therefore, couples need to be offered genetic counseling at a preconception visit or early in pregnancy. Although penetrance of DD is complete, spontaneous mutations are frequent and expressivity is variable¹; prenatal diagnosis, though available since the 1980s, is therefore unreliable in DD, given the considerable variation in phenotypic expressivity. Differing phenotypes underscore the importance of proper counseling by the treating dermatologist or other provider. Females with a mild or nearly undetectable phenotype can give birth to a child with severe disease.

Lack of clear understanding about the variable phenotypic expressivity of DD can cause considerable anger, anxiety, guilt, psychological trauma, and fear in parents, should their child later develop a severe phenotype. They may feel that they were not properly prepared for the outcome. The physician-parent or physician-patient relationship can be negatively impacted if ongoing counseling is inadequate.

Clinically, DD presents in early adolescence (age range, 6–20 years) in most patients, which means that the disease and female reproductive years are contemporaneous. However, gynecologic and obstetric issues and complications of DD rarely have been addressed.³ Oromucosal involvement in DD is reported in 13% to 50% of cases, yet vaginal and cervical mucosal involvement rarely has been described,^4,5 likely due to underreporting. Therefore, in this rare disease, it is important to address these aspects so that the patients are provided with appropriate management options.

Implications for Cervical Screening and Papanicolaou Tests

Cytopathologic findings of a Papanicolaou test taken from a patient with DD can lead to erroneous diagnosis of a low-grade squamous intraepithelial lesion due to cervical involvement by the disease process; therefore, correct interpretation of a smear may be inappropriate and erroneous. The cytopathologist needs to be informed of the patient’s diagnosis of DD in advance for appropriate reporting.^5,6

Obstetric Implications

Fertility is normal in DD patients, and pregnancy usually has a normal course; however, exacerbation and remission of disease have been reported. de la Rosa Carrillo⁷ reported a case of vegetating DD during pregnancy. He described it as an exacerbation with concurrent bacterial infection and bilateral external otitis.⁷ Spouge et al⁸ reported a case of a 58-year-old woman who was the mother of 4 DD patients. She experienced an exacerbation of DD during all 6 pregnancies but improved immediately postpartum.⁸ Espy et al⁹ evaluated 8 cases of women with DD and described spontaneous improvement of the disorder during pregnancy (1 case) or while taking an oral contraceptive (3 cases).

Prenatal Counseling

Women with DD should be encouraged to talk to their dermatologist, obstetrician, or other provider of prenatal care regarding plans for pregnancy, labor, and delivery, as these events might be affected by the disorder. During pregnancy, careful monitoring and self-care remain essential. Simple measures to reduce the impact of irritants on DD during pregnancy include keeping the skin cool, using a soothing moisturizer, applying photoprotection, and using sunscreen. Treatment with systemic retinoids must be avoided if pregnancy is planned.

Warty plaques and papules of DD can involve flexures (groin, vulva, and perineum), with resultant malodor and pruritus¹⁰ as well as the potential for (drug resistant) secondary infection (eg, Staphylococcus aureus, group B Streptococcus, viruses [eg, Kaposi varicelliform eruption]). Skin swabs should be taken for culture and susceptibility testing, and infection should be treated at the earliest sign.

Management Concerns During Pregnancy and Delivery

Because the benefits of treating DD might outweigh risk in certain cases, thorough discussion with the patient about options is recommended, including the following concerns:

• Because mucocutaneous elasticity of the birth canal, including the vulva, perineum, and groin, is essential for nontraumatic vaginal delivery, it might be necessary to schedule an elective cesarean delivery in DD patients in whom these regions are involved.¹¹

• In females with lower abdominal lesions, using a Pfannenstiel-Kerr incision for cesarean delivery might be problematic.¹¹

• A single case report has described successful anesthetic management of labor, delivery, and postpartum care in a DD patient.¹² Involvement of the skin of the back might preclude safe administration of regional anesthesia; however, because DD lesions are considered noninfectious, the authors operatively administered a subarachnoid block at the L3-L4 interspace through a lesion-free area. Postpartum, the patient was observed in the intensive care unit. She and the baby remained stable; she did not develop infectious complications, including a central nervous system infection.¹²

•Mucosal involvement is relatively rare in DD and has not been reported to compromise airway management.⁸

Postnatal Considerations

Breastfeeding might have to be stopped early or withheld altogether if there is widespread involvement of the skin of the breast or the nipple.¹¹ Darier disease has been associated with neuropsychiatric manifestations, including major depression (30%), suicide attempts (13%), suicidal thoughts (31%), cyclothymia, bipolar disorder (4%), and epilepsy (3%).^13,14 Therefore, patients should be screened for postpartum psychiatric manifestations at an early follow-up visit.

Final Thoughts

Although the etiology of DD is well known, the gynelogic and obstretric implications of this genodermatosis have rarely been described. This brief commentary is an attempt to provide the important information to a practicing dermatologist for appropriate management of female DD patients.

Darier disease (DD)(also known as dyskeratosis follicularis) is a rare, autosomal-dominant genodermatosis characterized by greasy, rough, keratotic papules; typical nail abnormalities; mucosal changes; and characteristic dyskeratotic acantholysis that is called corps ronds and grains on histopathologic analysis. Darier disease is caused by mutations of the ATP2A2 gene on chromosome 12q23-24.^1,2

Because of the autosomal-dominant pattern of inheritance in DD, if either parent is affected by DD, approximately 50% of their offspring will have the disorder. Therefore, couples need to be offered genetic counseling at a preconception visit or early in pregnancy. Although penetrance of DD is complete, spontaneous mutations are frequent and expressivity is variable¹; prenatal diagnosis, though available since the 1980s, is therefore unreliable in DD, given the considerable variation in phenotypic expressivity. Differing phenotypes underscore the importance of proper counseling by the treating dermatologist or other provider. Females with a mild or nearly undetectable phenotype can give birth to a child with severe disease.

Lack of clear understanding about the variable phenotypic expressivity of DD can cause considerable anger, anxiety, guilt, psychological trauma, and fear in parents, should their child later develop a severe phenotype. They may feel that they were not properly prepared for the outcome. The physician-parent or physician-patient relationship can be negatively impacted if ongoing counseling is inadequate.

Clinically, DD presents in early adolescence (age range, 6–20 years) in most patients, which means that the disease and female reproductive years are contemporaneous. However, gynecologic and obstetric issues and complications of DD rarely have been addressed.³ Oromucosal involvement in DD is reported in 13% to 50% of cases, yet vaginal and cervical mucosal involvement rarely has been described,^4,5 likely due to underreporting. Therefore, in this rare disease, it is important to address these aspects so that the patients are provided with appropriate management options.

Implications for Cervical Screening and Papanicolaou Tests

Cytopathologic findings of a Papanicolaou test taken from a patient with DD can lead to erroneous diagnosis of a low-grade squamous intraepithelial lesion due to cervical involvement by the disease process; therefore, correct interpretation of a smear may be inappropriate and erroneous. The cytopathologist needs to be informed of the patient’s diagnosis of DD in advance for appropriate reporting.^5,6

Obstetric Implications

Fertility is normal in DD patients, and pregnancy usually has a normal course; however, exacerbation and remission of disease have been reported. de la Rosa Carrillo⁷ reported a case of vegetating DD during pregnancy. He described it as an exacerbation with concurrent bacterial infection and bilateral external otitis.⁷ Spouge et al⁸ reported a case of a 58-year-old woman who was the mother of 4 DD patients. She experienced an exacerbation of DD during all 6 pregnancies but improved immediately postpartum.⁸ Espy et al⁹ evaluated 8 cases of women with DD and described spontaneous improvement of the disorder during pregnancy (1 case) or while taking an oral contraceptive (3 cases).

Prenatal Counseling

Women with DD should be encouraged to talk to their dermatologist, obstetrician, or other provider of prenatal care regarding plans for pregnancy, labor, and delivery, as these events might be affected by the disorder. During pregnancy, careful monitoring and self-care remain essential. Simple measures to reduce the impact of irritants on DD during pregnancy include keeping the skin cool, using a soothing moisturizer, applying photoprotection, and using sunscreen. Treatment with systemic retinoids must be avoided if pregnancy is planned.

Warty plaques and papules of DD can involve flexures (groin, vulva, and perineum), with resultant malodor and pruritus¹⁰ as well as the potential for (drug resistant) secondary infection (eg, Staphylococcus aureus, group B Streptococcus, viruses [eg, Kaposi varicelliform eruption]). Skin swabs should be taken for culture and susceptibility testing, and infection should be treated at the earliest sign.

Management Concerns During Pregnancy and Delivery

Because the benefits of treating DD might outweigh risk in certain cases, thorough discussion with the patient about options is recommended, including the following concerns:

• Because mucocutaneous elasticity of the birth canal, including the vulva, perineum, and groin, is essential for nontraumatic vaginal delivery, it might be necessary to schedule an elective cesarean delivery in DD patients in whom these regions are involved.¹¹

• In females with lower abdominal lesions, using a Pfannenstiel-Kerr incision for cesarean delivery might be problematic.¹¹

• A single case report has described successful anesthetic management of labor, delivery, and postpartum care in a DD patient.¹² Involvement of the skin of the back might preclude safe administration of regional anesthesia; however, because DD lesions are considered noninfectious, the authors operatively administered a subarachnoid block at the L3-L4 interspace through a lesion-free area. Postpartum, the patient was observed in the intensive care unit. She and the baby remained stable; she did not develop infectious complications, including a central nervous system infection.¹²

•Mucosal involvement is relatively rare in DD and has not been reported to compromise airway management.⁸

Postnatal Considerations

Breastfeeding might have to be stopped early or withheld altogether if there is widespread involvement of the skin of the breast or the nipple.¹¹ Darier disease has been associated with neuropsychiatric manifestations, including major depression (30%), suicide attempts (13%), suicidal thoughts (31%), cyclothymia, bipolar disorder (4%), and epilepsy (3%).^13,14 Therefore, patients should be screened for postpartum psychiatric manifestations at an early follow-up visit.

Final Thoughts

Although the etiology of DD is well known, the gynelogic and obstretric implications of this genodermatosis have rarely been described. This brief commentary is an attempt to provide the important information to a practicing dermatologist for appropriate management of female DD patients.