Photolichenoid plaques with associated vitiliginous pigmentary changes.

A 49-year-old man with advanced HIV/AIDS on anti-retroviral therapy (HAART) and trimethoprim-sulfamethoxazole (TMP-SMX) presented with a several-month history of pruritic, erythematous, lichenified papules that coalesced into hyperkeratotic plaques on the trunk and extremities in a sun-exposed distribution. He shortly thereafter developed a progressive depigmentation over more than 80 percent of his body surface area. A biopsy specimen of an erythematous plaque on the trunk showed a superficial and mid-dermal infiltrate of lymphocytes with eosinophils, most consistent with either chronic lichenoid drug eruption or atypical lymphoproliferative disorder (ACLD) of HIV.

Acanthosis nigricans in the setting of niacin therapy.

We report the case of a 63-year-old obese man with a rapid-onset of widespread acanthosis nigricans (AN) in the setting of having recently initiated treatment with niacin for dyslipidemia. Although obesity and insulin-resistance are risk factors for AN, AN associated with endocrine dysfunction tends to have a more gradual onset and limited involvement. Owing to our patient's age, the rapid onset, and extensive distribution of his eruption, we initially were concerned about paraneoplastic AN.

Extramammary Paget disease.

We report the case of a 60-year-old man with penile-scrotal extramammary Paget disease (EMPD). The patient initially underwent Mohs micrographic surgery, but the margins remained positive after several sections; multiple scouting punch biopsies used to define the extent of the tumor were also positive. Because of concerns about functional impairment and cosmesis associated with wide local excision, the patient instead chose treatment with topical 5 percent imiquimod cream as a cytoreductive and margin-defining treatment.

Porokeratosis plantaris, palmaris, et disseminata.

We describe a 73-year-old woman with a long-standing history of annular, hyperkeratotic papules that began on the palms and soles and gradually spread to her trunk, extremities, and face. The clinical presentation and biopsy findings were consistent with PPPD, which is a rare subtype of porokeratosis that begins on the palms and soles and gradually spreads to the trunk and extremities. Owing to the risk of malignant degeneration in porokeratosis, patients should be closely monitored with total body skin examinations.

Conradi-Hünermann-Happle syndrome.

A seven-year-old girl was born with red, scaly skin that later evolved into hypopigmentation and follicular atrophoderma in a widespread distribution that followed Blaschko lines. She also had patchy, scarring alopecia, left microphthalmia, bilateral cataracts, dysmorphic facies, short stature, hip dysplasia, and vertebral abnormalities. An elevated plasma 8(9)-cholestenol level confirmed the diagnosis of Conradi-Hünermann-Happle syndrome, which is caused by mutations in the emopamil binding protein (EBP) gene.

Porokeratosis palmaris et plantaris disseminata or a disseminated late-onset variant of porokeratotic eccrine ostial and dermal ductal nevus (PEODDN) with follicular involvement.

A 48-year-old woman presented with a four-year history of pruritic, hyperkeratotic, spiny papules that began on her chest and spread to her extremities, groin, palms, face, and scalp where it caused non-scarring alopecia. Histopathologic features included cornoid lamella, which is the hallmark of porokeratosis. However, the patient's constellation of findings does not meet diagnostic criteria for any of the five clinical variants of porokeratosis.

Lip plumper contact urticaria.

Lip plumpers are relatively new topical agents on the market that are designed to increase lip volume minutes to days after application. In this report, we describe a case of lip plumper contact urticaria in a young boy. We also discuss the mechanisms of action of lip plumpers and the sociocultural reasons for their use.