Case Letter

To the Editor:

Cutaneous herpes simplex virus (HSV) infection generally involves mucocutaneous junctions, but virtually any area of the skin can be affected.¹ When the genital area of adult patients is affected, the disease usually is sexually transmitted and mainly caused by HSV-2. In infants, genital primary herpetic infection is rare and more commonly is caused by HSV-1 than by HSV-2. We report a rare case of genital primary herpetic infection with concurrent hepatitis in an infant.

An 8-month-old infant with no underlying medical problems, including atopic dermatitis, was referred for erythematous grouped vesicles with erosions on the perianal area of 4 days’ duration (Figure). The skin color appeared normal, not icterus. She also had a fever (temperature, 37.9 °C), and her urination pattern had changed from normal to frequent leakage, possibly owing to pain related to the eroded lesions. Physical examination did not reveal palpable inguinal lymph nodes. The oral mucosa was not involved. The patient’s father had a history of recurrent herpetic infection on both the perioral and perianal areas.

Although the possibility of systemic involvement including hepatitis due to HSV infection is low, awareness among dermatologists about primary herpetic infection and its possible complications would be helpful in the diagnosis and treatment, especially for atypical or extensive cases.

To the Editor:

Cutaneous herpes simplex virus (HSV) infection generally involves mucocutaneous junctions, but virtually any area of the skin can be affected.¹ When the genital area of adult patients is affected, the disease usually is sexually transmitted and mainly caused by HSV-2. In infants, genital primary herpetic infection is rare and more commonly is caused by HSV-1 than by HSV-2. We report a rare case of genital primary herpetic infection with concurrent hepatitis in an infant.

An 8-month-old infant with no underlying medical problems, including atopic dermatitis, was referred for erythematous grouped vesicles with erosions on the perianal area of 4 days’ duration (Figure). The skin color appeared normal, not icterus. She also had a fever (temperature, 37.9 °C), and her urination pattern had changed from normal to frequent leakage, possibly owing to pain related to the eroded lesions. Physical examination did not reveal palpable inguinal lymph nodes. The oral mucosa was not involved. The patient’s father had a history of recurrent herpetic infection on both the perioral and perianal areas.

Although the possibility of systemic involvement including hepatitis due to HSV infection is low, awareness among dermatologists about primary herpetic infection and its possible complications would be helpful in the diagnosis and treatment, especially for atypical or extensive cases.

To the Editor:

Cutaneous herpes simplex virus (HSV) infection generally involves mucocutaneous junctions, but virtually any area of the skin can be affected.¹ When the genital area of adult patients is affected, the disease usually is sexually transmitted and mainly caused by HSV-2. In infants, genital primary herpetic infection is rare and more commonly is caused by HSV-1 than by HSV-2. We report a rare case of genital primary herpetic infection with concurrent hepatitis in an infant.

An 8-month-old infant with no underlying medical problems, including atopic dermatitis, was referred for erythematous grouped vesicles with erosions on the perianal area of 4 days’ duration (Figure). The skin color appeared normal, not icterus. She also had a fever (temperature, 37.9 °C), and her urination pattern had changed from normal to frequent leakage, possibly owing to pain related to the eroded lesions. Physical examination did not reveal palpable inguinal lymph nodes. The oral mucosa was not involved. The patient’s father had a history of recurrent herpetic infection on both the perioral and perianal areas.

Although the possibility of systemic involvement including hepatitis due to HSV infection is low, awareness among dermatologists about primary herpetic infection and its possible complications would be helpful in the diagnosis and treatment, especially for atypical or extensive cases.

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.

To the Editor:

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition with high morbidity rates. Symptoms typically develop between puberty and the third decade of life, affecting twice as many females as males, with an overall disease prevalence of 1% to 4%.¹ The pathogenesis is theorized to be related to an immune response to follicular occlusion and rupture in genetically susceptible individuals.

Among the complications associated with HS, the development of cutaneous squamous cell carcinoma (SCC) is 4.6-times more likely within HS lesions than in normal skin and typically is seen in the setting of long-standing disease, particularly in men with HS lesions located on the buttocks and genital region for more than 20 years.² In 2015, the tumor necrosis factor (TNF) inhibitor adalimumab was approved by the US Food and Drug Administration for the treatment of HS. Tumor necrosis factor α inhibitors have been associated with an increased risk for skin cancer in other clinical settings.^3,4 We present a case of locally advanced SCC that developed in a patient with HS who was treated with adalimumab and infliximab (both TNF-α inhibitors), ultimately leading to the patient’s death.

A 59-year-old man who smoked with a 40-year history of severe HS, who previously was lost to follow-up, presented to our dermatology clinic with lesions on the buttocks. Physical examination demonstrated confluent, indurated, boggy plaques; scattered sinus tracts with purulent drainage; scattered cystlike nodules; and tenderness to palpation consistent with Hurley stage III disease (Figure 1A). No involvement of the axillae or groin was noted. He was started on doxycycline and a prednisone taper with minimal improvement and subsequently was switched to adalimumab 3 months later. Adalimumab provided little relief and was discontinued; therapy was transitioned to infliximab 3 months later.

To the Editor:

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition with high morbidity rates. Symptoms typically develop between puberty and the third decade of life, affecting twice as many females as males, with an overall disease prevalence of 1% to 4%.¹ The pathogenesis is theorized to be related to an immune response to follicular occlusion and rupture in genetically susceptible individuals.

Among the complications associated with HS, the development of cutaneous squamous cell carcinoma (SCC) is 4.6-times more likely within HS lesions than in normal skin and typically is seen in the setting of long-standing disease, particularly in men with HS lesions located on the buttocks and genital region for more than 20 years.² In 2015, the tumor necrosis factor (TNF) inhibitor adalimumab was approved by the US Food and Drug Administration for the treatment of HS. Tumor necrosis factor α inhibitors have been associated with an increased risk for skin cancer in other clinical settings.^3,4 We present a case of locally advanced SCC that developed in a patient with HS who was treated with adalimumab and infliximab (both TNF-α inhibitors), ultimately leading to the patient’s death.

A 59-year-old man who smoked with a 40-year history of severe HS, who previously was lost to follow-up, presented to our dermatology clinic with lesions on the buttocks. Physical examination demonstrated confluent, indurated, boggy plaques; scattered sinus tracts with purulent drainage; scattered cystlike nodules; and tenderness to palpation consistent with Hurley stage III disease (Figure 1A). No involvement of the axillae or groin was noted. He was started on doxycycline and a prednisone taper with minimal improvement and subsequently was switched to adalimumab 3 months later. Adalimumab provided little relief and was discontinued; therapy was transitioned to infliximab 3 months later.

To the Editor:

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition with high morbidity rates. Symptoms typically develop between puberty and the third decade of life, affecting twice as many females as males, with an overall disease prevalence of 1% to 4%.¹ The pathogenesis is theorized to be related to an immune response to follicular occlusion and rupture in genetically susceptible individuals.

Among the complications associated with HS, the development of cutaneous squamous cell carcinoma (SCC) is 4.6-times more likely within HS lesions than in normal skin and typically is seen in the setting of long-standing disease, particularly in men with HS lesions located on the buttocks and genital region for more than 20 years.² In 2015, the tumor necrosis factor (TNF) inhibitor adalimumab was approved by the US Food and Drug Administration for the treatment of HS. Tumor necrosis factor α inhibitors have been associated with an increased risk for skin cancer in other clinical settings.^3,4 We present a case of locally advanced SCC that developed in a patient with HS who was treated with adalimumab and infliximab (both TNF-α inhibitors), ultimately leading to the patient’s death.

A 59-year-old man who smoked with a 40-year history of severe HS, who previously was lost to follow-up, presented to our dermatology clinic with lesions on the buttocks. Physical examination demonstrated confluent, indurated, boggy plaques; scattered sinus tracts with purulent drainage; scattered cystlike nodules; and tenderness to palpation consistent with Hurley stage III disease (Figure 1A). No involvement of the axillae or groin was noted. He was started on doxycycline and a prednisone taper with minimal improvement and subsequently was switched to adalimumab 3 months later. Adalimumab provided little relief and was discontinued; therapy was transitioned to infliximab 3 months later.

To the Editor:

Lichen planus (LP) is an inflammatory mucocutaneous disorder that primarily affects adults aged 30 to 60 years.¹ It can present across various regions such as the skin, scalp, oral cavity, genitalia, nails, and hair. It classically presents with pruritic, purple, polygonal papules or plaques. The proposed pathogenesis of this condition involves autoimmune destruction of epidermal basal keratinocytes.² Management involves a stepwise approach, beginning with topical therapies such as corticosteroids and phototherapy and proceeding to systemic therapy including oral corticosteroids and retinoids. Additional medications with reported positive results include immunomodulators such as cyclosporine, tacrolimus, and mycophenolate mofetil.^2-4 Dupilumab is a biologic immunomodulator and antagonist to the IL-4Rα on helper T cells (T_H1). Although indicated for the treatment of moderate to severe atopic dermatitis, this medication’s immunomodulatory properties have been shown to aid various inflammatory cutaneous conditions, including prurigo nodularis.^5-9 We present a case of dupilumab therapy for treatment-refractory LP.

A 52-year-old man presented with a new-onset progressive rash over the prior 6 months. He reported no history of atopic dermatitis. The patient described the rash as “severely pruritic” with a numeric rating scale itch intensity of 9/10 (0 being no itch; 10 being the worst itch imaginable). Physical examination revealed purple polygonal scaly papules on the arms, hands, legs, feet, chest, and back (Figure 1).

Treatment-refractory LP remains difficult to manage for both the patient and provider. Treatment regimens remain limited to small uncontrolled studies and case reports. Although primarily considered a T_H1-mediated disease, the interplay of various alternative signaling pathways has been suggested. Our case of dupilumab-responsive LP suggests an underlying pathologic role of T_H2-mediated activity. Dupilumab shows promise as an effective therapy for refractory LP, as evidenced by our patient’s remarkable response. Larger studies are warranted regarding the role of T_H2-mediated inflammation and the use of dupilumab in LP.

To the Editor:

Lichen planus (LP) is an inflammatory mucocutaneous disorder that primarily affects adults aged 30 to 60 years.¹ It can present across various regions such as the skin, scalp, oral cavity, genitalia, nails, and hair. It classically presents with pruritic, purple, polygonal papules or plaques. The proposed pathogenesis of this condition involves autoimmune destruction of epidermal basal keratinocytes.² Management involves a stepwise approach, beginning with topical therapies such as corticosteroids and phototherapy and proceeding to systemic therapy including oral corticosteroids and retinoids. Additional medications with reported positive results include immunomodulators such as cyclosporine, tacrolimus, and mycophenolate mofetil.^2-4 Dupilumab is a biologic immunomodulator and antagonist to the IL-4Rα on helper T cells (T_H1). Although indicated for the treatment of moderate to severe atopic dermatitis, this medication’s immunomodulatory properties have been shown to aid various inflammatory cutaneous conditions, including prurigo nodularis.^5-9 We present a case of dupilumab therapy for treatment-refractory LP.

A 52-year-old man presented with a new-onset progressive rash over the prior 6 months. He reported no history of atopic dermatitis. The patient described the rash as “severely pruritic” with a numeric rating scale itch intensity of 9/10 (0 being no itch; 10 being the worst itch imaginable). Physical examination revealed purple polygonal scaly papules on the arms, hands, legs, feet, chest, and back (Figure 1).

Treatment-refractory LP remains difficult to manage for both the patient and provider. Treatment regimens remain limited to small uncontrolled studies and case reports. Although primarily considered a T_H1-mediated disease, the interplay of various alternative signaling pathways has been suggested. Our case of dupilumab-responsive LP suggests an underlying pathologic role of T_H2-mediated activity. Dupilumab shows promise as an effective therapy for refractory LP, as evidenced by our patient’s remarkable response. Larger studies are warranted regarding the role of T_H2-mediated inflammation and the use of dupilumab in LP.

To the Editor:

Lichen planus (LP) is an inflammatory mucocutaneous disorder that primarily affects adults aged 30 to 60 years.¹ It can present across various regions such as the skin, scalp, oral cavity, genitalia, nails, and hair. It classically presents with pruritic, purple, polygonal papules or plaques. The proposed pathogenesis of this condition involves autoimmune destruction of epidermal basal keratinocytes.² Management involves a stepwise approach, beginning with topical therapies such as corticosteroids and phototherapy and proceeding to systemic therapy including oral corticosteroids and retinoids. Additional medications with reported positive results include immunomodulators such as cyclosporine, tacrolimus, and mycophenolate mofetil.^2-4 Dupilumab is a biologic immunomodulator and antagonist to the IL-4Rα on helper T cells (T_H1). Although indicated for the treatment of moderate to severe atopic dermatitis, this medication’s immunomodulatory properties have been shown to aid various inflammatory cutaneous conditions, including prurigo nodularis.^5-9 We present a case of dupilumab therapy for treatment-refractory LP.

A 52-year-old man presented with a new-onset progressive rash over the prior 6 months. He reported no history of atopic dermatitis. The patient described the rash as “severely pruritic” with a numeric rating scale itch intensity of 9/10 (0 being no itch; 10 being the worst itch imaginable). Physical examination revealed purple polygonal scaly papules on the arms, hands, legs, feet, chest, and back (Figure 1).

Treatment-refractory LP remains difficult to manage for both the patient and provider. Treatment regimens remain limited to small uncontrolled studies and case reports. Although primarily considered a T_H1-mediated disease, the interplay of various alternative signaling pathways has been suggested. Our case of dupilumab-responsive LP suggests an underlying pathologic role of T_H2-mediated activity. Dupilumab shows promise as an effective therapy for refractory LP, as evidenced by our patient’s remarkable response. Larger studies are warranted regarding the role of T_H2-mediated inflammation and the use of dupilumab in LP.

To the Editor:

Erosive lichen planus (LP) often is painful, debilitating, and resistant to topical therapy making it both a diagnostic and therapeutic challenge. We report the case of an elderly woman with isolated perianal erosive LP, a rare clinical manifestation. We also review cases of erosive perianal LP reported in the literature.

A 72-year-old woman was referred to our dermatology clinic for evaluation of multiple pruritic and painful perianal lesions of 1 year’s duration. The lesions had remained stable since onset, with no other reported lesions elsewhere on body, including the mucosae. Her medical history was notable for rheumatoid arthritis, osteoporosis, hypercholesterolemia, and hypertension. She was taking methotrexate, folic acid, abatacept, alendronate, atorvastatin, and lisinopril. The patient reported she had been using abatacept for 3 years and lisinopril for 2 years. Her primary care physician initially treated the lesions as hemorrhoids but referred her to a gastroenterologist when they failed to improve. Gastroenterology evaluated the patient, and a colonoscopy was performed with unremarkable results. Thus, she was referred to dermatology for further evaluation.

Physical examination revealed 2 tender, sharply defined, angulated erosions with irregular violaceous borders involving the perianal skin (Figure 1). A biopsy of one of the lesions was taken. Histopathologic examination revealed acanthosis of the epidermis with slight compact hyperkeratosis, scattered dyskeratotic keratinocytes, and a dense bandlike lymphohistiocytic infiltrate that obliterated the dermoepidermal junction (Figure 2). A diagnosis of perianal erosive LP was made. The patient was prescribed mometasone ointment 0.1% daily with notable improvement after 2 months.

Treatment of LP varies depending on the location and subtype of the lesions and is primarily aimed at improving symptoms. Topical corticosteroids are the standard treatment of LP; however, there is limited evidence regarding their efficacy for mucosal LP. Although randomized controlled trials assessing the efficacy of different interventions on oral erosive LP are available in the literature,¹⁵ there is a paucity of studies addressing this topic for genital or perianal LP. A review of the literature regarding perianal erosive LP suggests good response to high-potency topical steroids and calcineurin inhibitors with resolution of lesions within 3 to 4 weeks.^11,15-18

Erosive LP is a painful variant that can cause erosions, ulcerations, and scarring. It rarely is seen in the perianal region alone and presents a diagnostic challenge. Treatment with high-potency topical steroid therapy seems to be effective in the few cases that have been reported as well as in our case. More comprehensive data from randomized controlled trials would be needed to evaluate their efficacy compared to other therapies.

To the Editor:

Erosive lichen planus (LP) often is painful, debilitating, and resistant to topical therapy making it both a diagnostic and therapeutic challenge. We report the case of an elderly woman with isolated perianal erosive LP, a rare clinical manifestation. We also review cases of erosive perianal LP reported in the literature.

A 72-year-old woman was referred to our dermatology clinic for evaluation of multiple pruritic and painful perianal lesions of 1 year’s duration. The lesions had remained stable since onset, with no other reported lesions elsewhere on body, including the mucosae. Her medical history was notable for rheumatoid arthritis, osteoporosis, hypercholesterolemia, and hypertension. She was taking methotrexate, folic acid, abatacept, alendronate, atorvastatin, and lisinopril. The patient reported she had been using abatacept for 3 years and lisinopril for 2 years. Her primary care physician initially treated the lesions as hemorrhoids but referred her to a gastroenterologist when they failed to improve. Gastroenterology evaluated the patient, and a colonoscopy was performed with unremarkable results. Thus, she was referred to dermatology for further evaluation.

Physical examination revealed 2 tender, sharply defined, angulated erosions with irregular violaceous borders involving the perianal skin (Figure 1). A biopsy of one of the lesions was taken. Histopathologic examination revealed acanthosis of the epidermis with slight compact hyperkeratosis, scattered dyskeratotic keratinocytes, and a dense bandlike lymphohistiocytic infiltrate that obliterated the dermoepidermal junction (Figure 2). A diagnosis of perianal erosive LP was made. The patient was prescribed mometasone ointment 0.1% daily with notable improvement after 2 months.

Treatment of LP varies depending on the location and subtype of the lesions and is primarily aimed at improving symptoms. Topical corticosteroids are the standard treatment of LP; however, there is limited evidence regarding their efficacy for mucosal LP. Although randomized controlled trials assessing the efficacy of different interventions on oral erosive LP are available in the literature,¹⁵ there is a paucity of studies addressing this topic for genital or perianal LP. A review of the literature regarding perianal erosive LP suggests good response to high-potency topical steroids and calcineurin inhibitors with resolution of lesions within 3 to 4 weeks.^11,15-18

Erosive LP is a painful variant that can cause erosions, ulcerations, and scarring. It rarely is seen in the perianal region alone and presents a diagnostic challenge. Treatment with high-potency topical steroid therapy seems to be effective in the few cases that have been reported as well as in our case. More comprehensive data from randomized controlled trials would be needed to evaluate their efficacy compared to other therapies.

To the Editor:

Erosive lichen planus (LP) often is painful, debilitating, and resistant to topical therapy making it both a diagnostic and therapeutic challenge. We report the case of an elderly woman with isolated perianal erosive LP, a rare clinical manifestation. We also review cases of erosive perianal LP reported in the literature.

A 72-year-old woman was referred to our dermatology clinic for evaluation of multiple pruritic and painful perianal lesions of 1 year’s duration. The lesions had remained stable since onset, with no other reported lesions elsewhere on body, including the mucosae. Her medical history was notable for rheumatoid arthritis, osteoporosis, hypercholesterolemia, and hypertension. She was taking methotrexate, folic acid, abatacept, alendronate, atorvastatin, and lisinopril. The patient reported she had been using abatacept for 3 years and lisinopril for 2 years. Her primary care physician initially treated the lesions as hemorrhoids but referred her to a gastroenterologist when they failed to improve. Gastroenterology evaluated the patient, and a colonoscopy was performed with unremarkable results. Thus, she was referred to dermatology for further evaluation.

Physical examination revealed 2 tender, sharply defined, angulated erosions with irregular violaceous borders involving the perianal skin (Figure 1). A biopsy of one of the lesions was taken. Histopathologic examination revealed acanthosis of the epidermis with slight compact hyperkeratosis, scattered dyskeratotic keratinocytes, and a dense bandlike lymphohistiocytic infiltrate that obliterated the dermoepidermal junction (Figure 2). A diagnosis of perianal erosive LP was made. The patient was prescribed mometasone ointment 0.1% daily with notable improvement after 2 months.

Treatment of LP varies depending on the location and subtype of the lesions and is primarily aimed at improving symptoms. Topical corticosteroids are the standard treatment of LP; however, there is limited evidence regarding their efficacy for mucosal LP. Although randomized controlled trials assessing the efficacy of different interventions on oral erosive LP are available in the literature,¹⁵ there is a paucity of studies addressing this topic for genital or perianal LP. A review of the literature regarding perianal erosive LP suggests good response to high-potency topical steroids and calcineurin inhibitors with resolution of lesions within 3 to 4 weeks.^11,15-18

Erosive LP is a painful variant that can cause erosions, ulcerations, and scarring. It rarely is seen in the perianal region alone and presents a diagnostic challenge. Treatment with high-potency topical steroid therapy seems to be effective in the few cases that have been reported as well as in our case. More comprehensive data from randomized controlled trials would be needed to evaluate their efficacy compared to other therapies.

To the Editor:

A 7-day-old full-term infant presented to the neonatal intensive care unit with poor feeding and altered consciousness. She was born at 39 weeks and 3 days to a gravida 1 mother with a pregnancy history complicated by maternal chorioamnionitis and gestational diabetes. During labor, nonreassuring fetal heart tones and arrest of labor prompted an uncomplicated cesarean delivery with normal Apgar scores at birth. The infant’s family history revealed only beta thalassemia minor in her father. At 5 to 7 days of life, the mother noted difficulty with feeding and poor latch along with lethargy and depressed consciousness in the infant.

Upon arrival to the neonatal intensive care unit, the infant was noted to have rhythmic lip-smacking behavior, intermittent nystagmus, mild hypotonia, and clonic movements of the left upper extremity. An electroencephalogram was markedly abnormal, capturing multiple seizures in the bilateral cortical hemispheres. She was loaded with phenobarbital with no further seizure activity. Brain magnetic resonance imaging revealed innumerable punctate foci of restricted diffusion with corresponding punctate hemorrhage within the frontal and parietal white matter, as well as cortical diffusion restriction within the occipital lobe, inferior temporal lobe, bilateral thalami, and corpus callosum (Figure 1). An exhaustive infectious workup also was completed and was unremarkable, though she was treated with broad-spectrum antimicrobials, including intravenous acyclovir.

Incontinentia pigmenti, also known as Bloch-Sulzberger syndrome, is a rare multisystem neuroectodermal disorder, primarily affecting the skin, central nervous system (CNS), and retinas. The disorder can be inherited in an X-linked dominant fashion and appears almost exclusively in women with typical in utero lethality seen in males. Most affected individuals have a sporadic, or de novo, mutation, which was likely the case in our patient given that her mother demonstrated no signs or symptoms.¹ The pathogenesis of disease is a defect at chromosome Xq28 that is a region encoding the nuclear factor–κB essential modulator, IKBKG. Absence or mutation of IKBKG in IP results in failure to activate nuclear factor–κB and leaves cells vulnerable to cytokine-mediated apoptosis, especially after exposure to tumor necrosis factor α.²

Clinical manifestations of IP are present at or soon after birth. The cutaneous findings of this disorder are classically described as a step-wise progression through 4 distinct stages: (1) a linear and/or whorled vesicular eruption predominantly on the extremities at birth or within the first few weeks of life; (2) thickened linear or whorled verrucous plaques; (3) hyperpigmented streaks and whorls that may or may not correspond with prior affected areas that may resolve by adolescence; and (4) hypopigmented, possibly atrophic plaques on the extremities that may persist lifelong. Importantly, not every patient will experience each of these stages. Overlap can occur, and the time course of each stage is highly variable. Other ectodermal manifestations include dental abnormalities such as small, misshaped, or missing teeth; alopecia; and nail abnormalities. Ocular abnormalities associated with IP primarily occur in the retina, including vascular occlusion, neovascularization, hemorrhages, foveal abnormalities, as well as exudative and tractional detachments.^3,4

It is crucial to recognize CNS anomalies in association with the cutaneous findings of IP, as CNS pathology can be severe with profound developmental implications. Central nervous system findings have been noted to correlate with the appearance of the vesicular stage of IP. A high index of suspicion is needed, as the disease can demonstrate progression within a short time.^5-8 The most frequent anomalies include seizures, motor impairment, intellectual disability, and microcephaly.^9,10 Some of the most commonly identified CNS lesions on imaging include necrosis or brain infarcts, atrophy, and lesions of the corpus callosum.⁷

The pathogenesis of observed CNS changes in IP is not well understood. There have been numerous proposals of a vascular mechanism, and a microangiopathic process appears to be most plausible. Mutations in IKBKG may result in interruption of signaling via vascular endothelial growth factor receptor 3 with a consequent impact on angiogenesis, supporting a vascular mechanism. Additionally, mutations in IKBKG lead to activation of eotaxin, an eosinophil-selective chemokine.⁹ Eotaxin activation results in eosinophilic degranulation that mediates the classic eosinophilic infiltrate seen in the classic skin histology of IP. Additionally, it has been shown that eotaxin is strongly expressed by endothelial cells in IP, and more abundant eosinophil degranulation may play a role in mediating vaso-occlusion.⁷ Other studies have found that the highest expression level of the IKBKG gene is in the CNS, potentially explaining the extensive imaging findings of hemorrhage and diffusion restriction in our patient. These features likely are attributable to apoptosis of cells possessing the mutated IKBKG gene.^9-11

To the Editor:

A 7-day-old full-term infant presented to the neonatal intensive care unit with poor feeding and altered consciousness. She was born at 39 weeks and 3 days to a gravida 1 mother with a pregnancy history complicated by maternal chorioamnionitis and gestational diabetes. During labor, nonreassuring fetal heart tones and arrest of labor prompted an uncomplicated cesarean delivery with normal Apgar scores at birth. The infant’s family history revealed only beta thalassemia minor in her father. At 5 to 7 days of life, the mother noted difficulty with feeding and poor latch along with lethargy and depressed consciousness in the infant.

Upon arrival to the neonatal intensive care unit, the infant was noted to have rhythmic lip-smacking behavior, intermittent nystagmus, mild hypotonia, and clonic movements of the left upper extremity. An electroencephalogram was markedly abnormal, capturing multiple seizures in the bilateral cortical hemispheres. She was loaded with phenobarbital with no further seizure activity. Brain magnetic resonance imaging revealed innumerable punctate foci of restricted diffusion with corresponding punctate hemorrhage within the frontal and parietal white matter, as well as cortical diffusion restriction within the occipital lobe, inferior temporal lobe, bilateral thalami, and corpus callosum (Figure 1). An exhaustive infectious workup also was completed and was unremarkable, though she was treated with broad-spectrum antimicrobials, including intravenous acyclovir.

Incontinentia pigmenti, also known as Bloch-Sulzberger syndrome, is a rare multisystem neuroectodermal disorder, primarily affecting the skin, central nervous system (CNS), and retinas. The disorder can be inherited in an X-linked dominant fashion and appears almost exclusively in women with typical in utero lethality seen in males. Most affected individuals have a sporadic, or de novo, mutation, which was likely the case in our patient given that her mother demonstrated no signs or symptoms.¹ The pathogenesis of disease is a defect at chromosome Xq28 that is a region encoding the nuclear factor–κB essential modulator, IKBKG. Absence or mutation of IKBKG in IP results in failure to activate nuclear factor–κB and leaves cells vulnerable to cytokine-mediated apoptosis, especially after exposure to tumor necrosis factor α.²

Clinical manifestations of IP are present at or soon after birth. The cutaneous findings of this disorder are classically described as a step-wise progression through 4 distinct stages: (1) a linear and/or whorled vesicular eruption predominantly on the extremities at birth or within the first few weeks of life; (2) thickened linear or whorled verrucous plaques; (3) hyperpigmented streaks and whorls that may or may not correspond with prior affected areas that may resolve by adolescence; and (4) hypopigmented, possibly atrophic plaques on the extremities that may persist lifelong. Importantly, not every patient will experience each of these stages. Overlap can occur, and the time course of each stage is highly variable. Other ectodermal manifestations include dental abnormalities such as small, misshaped, or missing teeth; alopecia; and nail abnormalities. Ocular abnormalities associated with IP primarily occur in the retina, including vascular occlusion, neovascularization, hemorrhages, foveal abnormalities, as well as exudative and tractional detachments.^3,4

It is crucial to recognize CNS anomalies in association with the cutaneous findings of IP, as CNS pathology can be severe with profound developmental implications. Central nervous system findings have been noted to correlate with the appearance of the vesicular stage of IP. A high index of suspicion is needed, as the disease can demonstrate progression within a short time.^5-8 The most frequent anomalies include seizures, motor impairment, intellectual disability, and microcephaly.^9,10 Some of the most commonly identified CNS lesions on imaging include necrosis or brain infarcts, atrophy, and lesions of the corpus callosum.⁷

The pathogenesis of observed CNS changes in IP is not well understood. There have been numerous proposals of a vascular mechanism, and a microangiopathic process appears to be most plausible. Mutations in IKBKG may result in interruption of signaling via vascular endothelial growth factor receptor 3 with a consequent impact on angiogenesis, supporting a vascular mechanism. Additionally, mutations in IKBKG lead to activation of eotaxin, an eosinophil-selective chemokine.⁹ Eotaxin activation results in eosinophilic degranulation that mediates the classic eosinophilic infiltrate seen in the classic skin histology of IP. Additionally, it has been shown that eotaxin is strongly expressed by endothelial cells in IP, and more abundant eosinophil degranulation may play a role in mediating vaso-occlusion.⁷ Other studies have found that the highest expression level of the IKBKG gene is in the CNS, potentially explaining the extensive imaging findings of hemorrhage and diffusion restriction in our patient. These features likely are attributable to apoptosis of cells possessing the mutated IKBKG gene.^9-11

To the Editor:

A 7-day-old full-term infant presented to the neonatal intensive care unit with poor feeding and altered consciousness. She was born at 39 weeks and 3 days to a gravida 1 mother with a pregnancy history complicated by maternal chorioamnionitis and gestational diabetes. During labor, nonreassuring fetal heart tones and arrest of labor prompted an uncomplicated cesarean delivery with normal Apgar scores at birth. The infant’s family history revealed only beta thalassemia minor in her father. At 5 to 7 days of life, the mother noted difficulty with feeding and poor latch along with lethargy and depressed consciousness in the infant.

Upon arrival to the neonatal intensive care unit, the infant was noted to have rhythmic lip-smacking behavior, intermittent nystagmus, mild hypotonia, and clonic movements of the left upper extremity. An electroencephalogram was markedly abnormal, capturing multiple seizures in the bilateral cortical hemispheres. She was loaded with phenobarbital with no further seizure activity. Brain magnetic resonance imaging revealed innumerable punctate foci of restricted diffusion with corresponding punctate hemorrhage within the frontal and parietal white matter, as well as cortical diffusion restriction within the occipital lobe, inferior temporal lobe, bilateral thalami, and corpus callosum (Figure 1). An exhaustive infectious workup also was completed and was unremarkable, though she was treated with broad-spectrum antimicrobials, including intravenous acyclovir.

Incontinentia pigmenti, also known as Bloch-Sulzberger syndrome, is a rare multisystem neuroectodermal disorder, primarily affecting the skin, central nervous system (CNS), and retinas. The disorder can be inherited in an X-linked dominant fashion and appears almost exclusively in women with typical in utero lethality seen in males. Most affected individuals have a sporadic, or de novo, mutation, which was likely the case in our patient given that her mother demonstrated no signs or symptoms.¹ The pathogenesis of disease is a defect at chromosome Xq28 that is a region encoding the nuclear factor–κB essential modulator, IKBKG. Absence or mutation of IKBKG in IP results in failure to activate nuclear factor–κB and leaves cells vulnerable to cytokine-mediated apoptosis, especially after exposure to tumor necrosis factor α.²

Clinical manifestations of IP are present at or soon after birth. The cutaneous findings of this disorder are classically described as a step-wise progression through 4 distinct stages: (1) a linear and/or whorled vesicular eruption predominantly on the extremities at birth or within the first few weeks of life; (2) thickened linear or whorled verrucous plaques; (3) hyperpigmented streaks and whorls that may or may not correspond with prior affected areas that may resolve by adolescence; and (4) hypopigmented, possibly atrophic plaques on the extremities that may persist lifelong. Importantly, not every patient will experience each of these stages. Overlap can occur, and the time course of each stage is highly variable. Other ectodermal manifestations include dental abnormalities such as small, misshaped, or missing teeth; alopecia; and nail abnormalities. Ocular abnormalities associated with IP primarily occur in the retina, including vascular occlusion, neovascularization, hemorrhages, foveal abnormalities, as well as exudative and tractional detachments.^3,4

It is crucial to recognize CNS anomalies in association with the cutaneous findings of IP, as CNS pathology can be severe with profound developmental implications. Central nervous system findings have been noted to correlate with the appearance of the vesicular stage of IP. A high index of suspicion is needed, as the disease can demonstrate progression within a short time.^5-8 The most frequent anomalies include seizures, motor impairment, intellectual disability, and microcephaly.^9,10 Some of the most commonly identified CNS lesions on imaging include necrosis or brain infarcts, atrophy, and lesions of the corpus callosum.⁷

The pathogenesis of observed CNS changes in IP is not well understood. There have been numerous proposals of a vascular mechanism, and a microangiopathic process appears to be most plausible. Mutations in IKBKG may result in interruption of signaling via vascular endothelial growth factor receptor 3 with a consequent impact on angiogenesis, supporting a vascular mechanism. Additionally, mutations in IKBKG lead to activation of eotaxin, an eosinophil-selective chemokine.⁹ Eotaxin activation results in eosinophilic degranulation that mediates the classic eosinophilic infiltrate seen in the classic skin histology of IP. Additionally, it has been shown that eotaxin is strongly expressed by endothelial cells in IP, and more abundant eosinophil degranulation may play a role in mediating vaso-occlusion.⁷ Other studies have found that the highest expression level of the IKBKG gene is in the CNS, potentially explaining the extensive imaging findings of hemorrhage and diffusion restriction in our patient. These features likely are attributable to apoptosis of cells possessing the mutated IKBKG gene.^9-11

To the Editor:

Cutaneous amyloidosis can be secondary to many causes. We describe a case of amyloidosis that was secondary to the deposition of an antiretroviral drug enfuvirtide and clinically presented as bullae over the anterior abdominal wall.

A 65-year-old man with HIV presented with pink vesicles and flaccid bullae on the anterolateral aspect of the lower abdomen (Figure 1) in areas of self-administered subcutaneous injections of enfuvirtide. He reported tissue swelling with a yellow discoloration immediately after injections that would spontaneously subside after a few minutes.

In summary, several types of cutaneous amyloidosis occur, including secondary cutaneous involvement by systemic amyloidosis and drug-induced amyloidosis, and notable histopathologic overlap exists between these types. Given the differing treatment requirements depending on the type of cutaneous amyloidosis, obtaining an appropriate clinical history, including the patient’s medication list, is important to ensure the correct diagnosis is reached. Protein analysis with mass spectrometry can be used if the nature of the amyloid remains indeterminate.

To the Editor:

Cutaneous amyloidosis can be secondary to many causes. We describe a case of amyloidosis that was secondary to the deposition of an antiretroviral drug enfuvirtide and clinically presented as bullae over the anterior abdominal wall.

A 65-year-old man with HIV presented with pink vesicles and flaccid bullae on the anterolateral aspect of the lower abdomen (Figure 1) in areas of self-administered subcutaneous injections of enfuvirtide. He reported tissue swelling with a yellow discoloration immediately after injections that would spontaneously subside after a few minutes.

In summary, several types of cutaneous amyloidosis occur, including secondary cutaneous involvement by systemic amyloidosis and drug-induced amyloidosis, and notable histopathologic overlap exists between these types. Given the differing treatment requirements depending on the type of cutaneous amyloidosis, obtaining an appropriate clinical history, including the patient’s medication list, is important to ensure the correct diagnosis is reached. Protein analysis with mass spectrometry can be used if the nature of the amyloid remains indeterminate.

To the Editor:

Cutaneous amyloidosis can be secondary to many causes. We describe a case of amyloidosis that was secondary to the deposition of an antiretroviral drug enfuvirtide and clinically presented as bullae over the anterior abdominal wall.

A 65-year-old man with HIV presented with pink vesicles and flaccid bullae on the anterolateral aspect of the lower abdomen (Figure 1) in areas of self-administered subcutaneous injections of enfuvirtide. He reported tissue swelling with a yellow discoloration immediately after injections that would spontaneously subside after a few minutes.

In summary, several types of cutaneous amyloidosis occur, including secondary cutaneous involvement by systemic amyloidosis and drug-induced amyloidosis, and notable histopathologic overlap exists between these types. Given the differing treatment requirements depending on the type of cutaneous amyloidosis, obtaining an appropriate clinical history, including the patient’s medication list, is important to ensure the correct diagnosis is reached. Protein analysis with mass spectrometry can be used if the nature of the amyloid remains indeterminate.

To the Editor:

Oral isotretinoin is a widely used treatment modality in dermatologic practice that is highly effective for severe and recalcitrant acne vulgaris in addition to other conditions. Its use is accompanied by a variety of side effects that are mainly mucocutaneous. These dose-dependent side effects are experienced by almost all patients treated with this medication.¹

A generally healthy 14-year-old adolescent girl presented with severe widespread erosions located in a linear pattern corresponding to areas of wax depilation on the shins and thighs (Figure). Approximately 5 months prior, the patient started oral isotretinoin 40 mg daily for severe and recalcitrant acne vulgaris. She was not taking other medications. After 4 months of treatment, during which the acne lesions improved and the patient experienced only mild xerosis and cheilitis, the dosage was increased to 60 mg daily. Three weeks later, the patient underwent wax depilation, which resulted in the erosions.

Dermatologists typically advise patients to avoid wax epilation while being treated with isotretinoin; however, some patients do not adhere to this recommendation. Also, there are dermatologists who are not aware of this potential side effect. In one survey (N=54), only 4% of consulting dermatologists were aware of this complication.² A PubMed search of articles indexed for MEDLINE using the terms isotretinoin and wax revealed that this severe side effect with isotretinoin has been reported only 4 times in the medical literature.^2-5 The fact that wax epilation should be avoided during isotretinoin treatment previously was not included in the prescribing information. It currently is included in the isotretinoin prescribing information⁶ with an indication not to perform wax depilation for 6 months after stopping treatment. This case should serve as a reminder to avoid wax depilation during isotretinoin treatment.

To the Editor:

Oral isotretinoin is a widely used treatment modality in dermatologic practice that is highly effective for severe and recalcitrant acne vulgaris in addition to other conditions. Its use is accompanied by a variety of side effects that are mainly mucocutaneous. These dose-dependent side effects are experienced by almost all patients treated with this medication.¹

A generally healthy 14-year-old adolescent girl presented with severe widespread erosions located in a linear pattern corresponding to areas of wax depilation on the shins and thighs (Figure). Approximately 5 months prior, the patient started oral isotretinoin 40 mg daily for severe and recalcitrant acne vulgaris. She was not taking other medications. After 4 months of treatment, during which the acne lesions improved and the patient experienced only mild xerosis and cheilitis, the dosage was increased to 60 mg daily. Three weeks later, the patient underwent wax depilation, which resulted in the erosions.

Dermatologists typically advise patients to avoid wax epilation while being treated with isotretinoin; however, some patients do not adhere to this recommendation. Also, there are dermatologists who are not aware of this potential side effect. In one survey (N=54), only 4% of consulting dermatologists were aware of this complication.² A PubMed search of articles indexed for MEDLINE using the terms isotretinoin and wax revealed that this severe side effect with isotretinoin has been reported only 4 times in the medical literature.^2-5 The fact that wax epilation should be avoided during isotretinoin treatment previously was not included in the prescribing information. It currently is included in the isotretinoin prescribing information⁶ with an indication not to perform wax depilation for 6 months after stopping treatment. This case should serve as a reminder to avoid wax depilation during isotretinoin treatment.

To the Editor:

Oral isotretinoin is a widely used treatment modality in dermatologic practice that is highly effective for severe and recalcitrant acne vulgaris in addition to other conditions. Its use is accompanied by a variety of side effects that are mainly mucocutaneous. These dose-dependent side effects are experienced by almost all patients treated with this medication.¹

A generally healthy 14-year-old adolescent girl presented with severe widespread erosions located in a linear pattern corresponding to areas of wax depilation on the shins and thighs (Figure). Approximately 5 months prior, the patient started oral isotretinoin 40 mg daily for severe and recalcitrant acne vulgaris. She was not taking other medications. After 4 months of treatment, during which the acne lesions improved and the patient experienced only mild xerosis and cheilitis, the dosage was increased to 60 mg daily. Three weeks later, the patient underwent wax depilation, which resulted in the erosions.

Dermatologists typically advise patients to avoid wax epilation while being treated with isotretinoin; however, some patients do not adhere to this recommendation. Also, there are dermatologists who are not aware of this potential side effect. In one survey (N=54), only 4% of consulting dermatologists were aware of this complication.² A PubMed search of articles indexed for MEDLINE using the terms isotretinoin and wax revealed that this severe side effect with isotretinoin has been reported only 4 times in the medical literature.^2-5 The fact that wax epilation should be avoided during isotretinoin treatment previously was not included in the prescribing information. It currently is included in the isotretinoin prescribing information⁶ with an indication not to perform wax depilation for 6 months after stopping treatment. This case should serve as a reminder to avoid wax depilation during isotretinoin treatment.

To the Editor:

A 65-year-old man with severe atherosclerotic disease developed multiple painful eschars on the lower abdomen, thighs, sacrum, and perineum. He initially presented with myocardial ischemia and claudication and underwent 3 cardiac catheterizations as well as stenting of the superficial femoral artery. Within 2 weeks, he developed exquisitely tender nodules on the lower abdomen, clinically presumed to be sites of enoxaparin injections. These lesions gradually expanded and ulcerated to involve the sacrum, buttock, perineum, and upper thighs (Figure 1). Two punch biopsies from ulcerated skin taken 10 days apart demonstrated necrosis of skin and subcutaneous fat without evidence of vasculitis, vasculopathy, emboli, or notable inflammation despite examination of multiple levels of all submitted tissue. A definitive cause for the ulcerations remained elusive with development of new lesions. A third incisional biopsy of a newly developed, nonulcerated, subcutaneous nodule performed 8 weeks after presentation revealed multiple cholesterol emboli (Figure 2). He was treated with warfarin and clopidogrel bisulfate as well as local wound care. The lesions slowly resolved over the next 4 to 6 months.

Cholesterol embolization syndrome occurs when disrupted atherosclerotic plaques embolize from large proximal arteries to more distal arterioles, resulting in ischemic damage to 1 or more organ systems.¹ It can occur spontaneously but often is a consequence of thrombolytic therapy, anticoagulation, and angioinvasive procedures.^2,3 Cutaneous manifestations include livedo reticularis, retiform purpura, nodules, and gangrene. Although livedo reticularis may extend from the legs to the trunk, gangrenous lesions predominantly involve the distal digits.

This case illustrates the challenge in diagnosis of cholesterol emboli, both clinically and histologically. Cutaneous lesions are morphologically variable and often occur with systemic manifestations, mimicking numerous conditions.¹ Lower extremity involvement is a well-known occurrence in cholesterol embolization (ie, blue toe syndrome); however, periumbilical and lumbosacral lesions have not been emphasized in the dermatologic or peripheral vascular literature. Our patient’s initial diagnosis was enoxaparin necrosis at abdominal injection sites; however, this unusual distribution of lesions was ultimately determined to be the consequence of cholesterol embolization from the inferior epigastric and superficial external pudendal arteries at the time of stenting of the superficial femoral artery. Proximal truncal involvement should be recognized as an atypical but important cutaneous manifestation to facilitate timely diagnosis and treatment.^4,5

Our patient’s course also highlights the potential need for multiple biopsies. Although the gold standard for diagnosis is histologic confirmation, a negative biopsy does not always exclude cholesterol emboli, and one should have a low threshold to perform additional biopsies in the appropriate clinical setting.

To the Editor:

A 65-year-old man with severe atherosclerotic disease developed multiple painful eschars on the lower abdomen, thighs, sacrum, and perineum. He initially presented with myocardial ischemia and claudication and underwent 3 cardiac catheterizations as well as stenting of the superficial femoral artery. Within 2 weeks, he developed exquisitely tender nodules on the lower abdomen, clinically presumed to be sites of enoxaparin injections. These lesions gradually expanded and ulcerated to involve the sacrum, buttock, perineum, and upper thighs (Figure 1). Two punch biopsies from ulcerated skin taken 10 days apart demonstrated necrosis of skin and subcutaneous fat without evidence of vasculitis, vasculopathy, emboli, or notable inflammation despite examination of multiple levels of all submitted tissue. A definitive cause for the ulcerations remained elusive with development of new lesions. A third incisional biopsy of a newly developed, nonulcerated, subcutaneous nodule performed 8 weeks after presentation revealed multiple cholesterol emboli (Figure 2). He was treated with warfarin and clopidogrel bisulfate as well as local wound care. The lesions slowly resolved over the next 4 to 6 months.

Cholesterol embolization syndrome occurs when disrupted atherosclerotic plaques embolize from large proximal arteries to more distal arterioles, resulting in ischemic damage to 1 or more organ systems.¹ It can occur spontaneously but often is a consequence of thrombolytic therapy, anticoagulation, and angioinvasive procedures.^2,3 Cutaneous manifestations include livedo reticularis, retiform purpura, nodules, and gangrene. Although livedo reticularis may extend from the legs to the trunk, gangrenous lesions predominantly involve the distal digits.

This case illustrates the challenge in diagnosis of cholesterol emboli, both clinically and histologically. Cutaneous lesions are morphologically variable and often occur with systemic manifestations, mimicking numerous conditions.¹ Lower extremity involvement is a well-known occurrence in cholesterol embolization (ie, blue toe syndrome); however, periumbilical and lumbosacral lesions have not been emphasized in the dermatologic or peripheral vascular literature. Our patient’s initial diagnosis was enoxaparin necrosis at abdominal injection sites; however, this unusual distribution of lesions was ultimately determined to be the consequence of cholesterol embolization from the inferior epigastric and superficial external pudendal arteries at the time of stenting of the superficial femoral artery. Proximal truncal involvement should be recognized as an atypical but important cutaneous manifestation to facilitate timely diagnosis and treatment.^4,5

Our patient’s course also highlights the potential need for multiple biopsies. Although the gold standard for diagnosis is histologic confirmation, a negative biopsy does not always exclude cholesterol emboli, and one should have a low threshold to perform additional biopsies in the appropriate clinical setting.

To the Editor:

A 65-year-old man with severe atherosclerotic disease developed multiple painful eschars on the lower abdomen, thighs, sacrum, and perineum. He initially presented with myocardial ischemia and claudication and underwent 3 cardiac catheterizations as well as stenting of the superficial femoral artery. Within 2 weeks, he developed exquisitely tender nodules on the lower abdomen, clinically presumed to be sites of enoxaparin injections. These lesions gradually expanded and ulcerated to involve the sacrum, buttock, perineum, and upper thighs (Figure 1). Two punch biopsies from ulcerated skin taken 10 days apart demonstrated necrosis of skin and subcutaneous fat without evidence of vasculitis, vasculopathy, emboli, or notable inflammation despite examination of multiple levels of all submitted tissue. A definitive cause for the ulcerations remained elusive with development of new lesions. A third incisional biopsy of a newly developed, nonulcerated, subcutaneous nodule performed 8 weeks after presentation revealed multiple cholesterol emboli (Figure 2). He was treated with warfarin and clopidogrel bisulfate as well as local wound care. The lesions slowly resolved over the next 4 to 6 months.

Cholesterol embolization syndrome occurs when disrupted atherosclerotic plaques embolize from large proximal arteries to more distal arterioles, resulting in ischemic damage to 1 or more organ systems.¹ It can occur spontaneously but often is a consequence of thrombolytic therapy, anticoagulation, and angioinvasive procedures.^2,3 Cutaneous manifestations include livedo reticularis, retiform purpura, nodules, and gangrene. Although livedo reticularis may extend from the legs to the trunk, gangrenous lesions predominantly involve the distal digits.

This case illustrates the challenge in diagnosis of cholesterol emboli, both clinically and histologically. Cutaneous lesions are morphologically variable and often occur with systemic manifestations, mimicking numerous conditions.¹ Lower extremity involvement is a well-known occurrence in cholesterol embolization (ie, blue toe syndrome); however, periumbilical and lumbosacral lesions have not been emphasized in the dermatologic or peripheral vascular literature. Our patient’s initial diagnosis was enoxaparin necrosis at abdominal injection sites; however, this unusual distribution of lesions was ultimately determined to be the consequence of cholesterol embolization from the inferior epigastric and superficial external pudendal arteries at the time of stenting of the superficial femoral artery. Proximal truncal involvement should be recognized as an atypical but important cutaneous manifestation to facilitate timely diagnosis and treatment.^4,5

Our patient’s course also highlights the potential need for multiple biopsies. Although the gold standard for diagnosis is histologic confirmation, a negative biopsy does not always exclude cholesterol emboli, and one should have a low threshold to perform additional biopsies in the appropriate clinical setting.