Hyperkeratotic Plantar Plaques in an HIV-Positive Patient

A 31-year-old woman with human immunodeficiency virus (HIV) and a history of pulmonary tuberculosis and oral herpes simplex presented with a 7-month history of hyperkeratotic plaques on the soles of her feet. The plaques were mildly tender on weight bearing but were otherwise asymptomatic. No change in size or number of lesions had occurred in the preceding several months. No history of widespread eruption or similar lesions elsewhere on the body could be elicited during the initial patient interview. The patient had discontinued her suppressive acyclovir therapy 2 months before her evaluation and was taking no other medications. Physical examination revealed 7 discrete hyperkeratotic plaques involving the soles and lateral margins of both feet (Figure 1). The plaques were surrounded by a thin rim of erythema and covered with a light-brown friable crust. No nail dystrophy or subungual debris was present. The results of the remainder of the physical examination, which included the palms, were unremarkable. Laboratory values were significant for leukopenia, mild anemia, and moderately elevated hepatic enzymes. The CD4 cell count was 0.08 3 10/L (80/μL). An initial mineral oil preparation revealed no organisms, and a potassium hydroxide preparation of skin scrapings was negative for fungal elements. Several punch biopsy specimens were obtained (Figure 2). What is your diagnosis?