Painful Papulonodule on the Foot of a Patient With Human Immunodeficiency Virus

Abstract

A man in his 50s with diagnoses of human immunodeficiency virus (HIV) infection, hepatitis B, and latent tuberculosis presented with a slow-growing nodule on the left foot. The lesion started 1 year prior as a tender red nodule on the medial aspect of his first metatarsophalangeal joint, which would enlarge and become painful approximately once a month (Figure , A). The patient reported that with manipulation, a clear-to-yellow material drained from the lesion. The patient denied any purulent drainage, additional skin lesions, fever, chills, or other systemic symptoms. His medications included efavirenz-emtricitabine-tenofovir disoproxil fumarate for his HIV, with the most recent absolute CD4-positive cell count of 341 cells/mm 3 (reference range, 263-2045 cells/mm 3 ), and recent completion of an 8-month course of isoniazid treatment after being exposed to tuberculosis. Physical examination demonstrated an erythematous papulonodule without warmth or drainage on the dorsal left great toe. No lymphadenopathy was appreciated. A punch biopsy was performed (Figure , B, C, and D) to help establish the diagnosis. H&E, original magnification ×4 B Clinical photograph A H&E, original magnification ×40 C Gram stain, original magnification ×40 D Figure. A, Clinical photograph of slow-growing red papulonodule on the left toe dorsal foot. B, Biopsy with hematoxylin-eosin (H&E) staining demonstrating acral skin with acute and chronic inflammation within the deep dermis. C, Higher magnification highlights eosinophilic material surrounding small cocci. D, Gram staining of the biopsy supported the diagnosis. WHAT IS YOUR DIAGNOSIS? A. Botryomycosis B. Cutaneous tuberculosis C. Digital mucous cyst D. Foreign-body reaction Clinical Review & Education