Cutaneous blastomycosis masquerading as pyoderma gangrenosum

Abstract

Cutaneous blastomycosis (CB) is associated with a variety of skin manifestations. Among other entities, CB may be mistaken for pyoderma gangrenosum due to overlap of findings on histopathologic examination. We report a case of CB, initially diagnosed as pyoderma gangrenosum and treated with steroids, leading to disseminated blastomycosis and acute respiratory distress syndrome (ARDS).

FIG 1

(A) Diff-Quik stain of the BAL fluid specimen demonstrating the broad-based budding yeast of Blastomyces dermatitidis. (B) The same specimen stained by the Gomori methenamine silver stain method. The double walls of the yeast form of this dimorphic pathogen are clearly visible in both stains. (C) Low-power (original magnification, ×100) examination of a hematoxylin-and-eosin-stained skin biopsy specimen demonstrates pseudoepitheliomatous hyperplasia and a predominately neutrophilic inflammatory infiltrate. (D) High-power magnification (original magnification, ×400) of the skin biopsy specimen reveals a broad-based budding yeast cell and adjacent yeast with thick, refractile double walls within a multinucleate giant cell.