The histopathologic findings included hyperkeratosis, pseudoepitheliomatous hyperplasia, and a granulomatous inflammatory reaction with microabscess formation. Spherical, brown sclerotic bodies were present in the inflammatory infiltrate (Figure 3). A silver stain confirmed the presence of fungal organisms. Tissue culture yielded Fonsecaea pedrosoi. Our patient is currently being treated with systemic terbinafine therapy combined with monthly cryotherapy. Some areas of regression have been noted.
Nonhealing Verrucous Plaque on the Forearm—Diagnosis. Arch Dermatol. 2005;141(11):1457-1462. doi:10.1001/archderm.141.11.1457-g