An 18-Month History of Dorsal Foot Lesions

Abstract

A 32-year-old Nigerian woman presented with dull pain, pruritus, and discoloration of the dorsal aspect of both feet for 18 months. Her medical history included a red blood cell transfusion as a child and 2 uncomplicated pregnancies.The lesions started as small papules on the dorsal right great toe and left third toe that gradually spread across the dorsum of her feet over the following 12 months. An over-thecounter antifungal ointment was unhelpful. Her primary care physician completed a biopsy, diagnosed verruca plantaris, and prescribed topical salicylic acid twice daily for 4 weeks. The lesions did not improve, and her foot pain worsened. Subsequent treatment with topical liquid nitrogen cryotherapy was ineffective.Three months after cryotherapy, the patient presented to the dermatology clinic regarding the lesions on her feet. The patient stated that the lesions had been stable in size for the previous 6 months, without bleeding, discharge, or change in color. She continued to have 6 of 10, dull, constant pain that was nonradiating, improved when she soaked her feet in water, and worsened with any type of topical pressure or wrapping. Physical examination revealed multiple well-circumscribed, scaly plaques with cobblestone surfaces on the dorsal aspects of the forefoot and midfoot bilaterally. Findings were more severe on the right and left hindfoot (Figure, left panel). On serologic testing, the patient was negative for HIV and positive for hepatitis C virus (HCV). A punch biopsy of the right foot lesion revealed psoriasiform epidermal hyperplasia, parakeratosis, eosinophils, papillary dermal inflammation, and intraepidermal necrosis (Figure, right panel).