Chromoblastomycosis

Chromoblastomycosis is a chronic granulomatous infection of the skin and subcutaneous tissue caused by several different dematiaceous fungi (ie, fungi containing pigment in the cell wall, whether melanin or melanin-like). The indolent infection begins with the cutaneous inoculation of fungi, usually through some portion of the fungal cell capable of reproduction or propagation (eg, conidia, mycelia), into exposed skin, typically due to trauma. The infection has wide morphologic variability but typically begins as a pink-to-red macule or papule and evolves in later stages to a verrucous, hyperkeratotic plaque, tumor, or nodule; ultimately, the slow-growing, warty (eg, cauliflower-like) lesions may ulcerate.  The disease is most common in tropical and subtropical areas, where it is endemic and a neglected tropical disease; as such, it should be most strongly considered in patients who have recently traveled to or originated from these areas. Diagnosis of chromoblastomycosis requires the identification of multicellular clusters of pigmented fungal cells, which produce a characteristic finding called sclerotic bodies (ie, muriform bodies, copper pennies, medlar bodies) on a potassium hydroxide stain or with histopathologic analysis of a skin biopsy. Although other differential diagnoses may include infectious and noninfectious verrucous lesions, the treatment of chromoblastomycosis includes surgical removal for mild disease and antifungal therapy for moderate-to-severe disease. If left untreated, chromoblastomycosis complications can include debilitating tissue fibrosis, squamous cell carcinoma in the site of prior infection, lymphedema, or secondary bacterial infection.