Pityriasis rubra pilaris: an unusual cutaneous complication of AIDS.

Pityriasis rubra pilaris is an uncommon hyperkeratotic, papulosquamous disorder that has been reported in patients infected by HIV. We recount a case of pityriasis rubra pilaris in an HIV-seropositive man. A 36-year-old man with a history of ulcerative colitis and recurrent otitis externa had diffuse psoriaform erythroderma. He was treated initially with methotrexate and isoretinoin without clinical improvement. Skin examination showed large, erythematous, orange, scaly patches on the upper extremities and thickening of the nail beds. The palms and soles were hyperkeratotic. Skin biopsy revealed changes that were consistent with pityriasis rubra pilaris. Six months before the onset of symptoms, results of an enzyme-linked immunosorbent assay (ELISA) and Western Blot assay for HIV were negative. Six months after symptoms, results of repeat enzyme-linked immunosorbent assay and Western blots for HIV were positive (CD4+ T-cell count = 200 cells/ mm3). Clinical course had been complicated by episodes of Staphylococcus aureus bacteremia, mucocutaneous candidiasis, and development of localized squamous cell carcinoma of the skin. The increased severity of pityriasis rubra pilaris should prompt clinicians to consider coinfection with HIV in patients who have disease that is refractory to treatment. Clinicians also should remain vigilant for the development of squamous cell carcinoma.