Chromoblastomycosis in Western Thailand

A man living in rural western Thailand presented with a well-demarcated pinkish plaque on the dorsal surface of the right hand, extending to several fingers ( Figure 1 ). Mild scale was present. The lesion was not pruritic or tender, and there was no sporotrichoid lymphadenopathy. The differential diagnosis included cutaneous deep fungal and atypical mycobacterial infections. A punch biopsy showed a mononuclear dermal infiltrate with multinucleated giant cells and scattered darkbrown, round sclerotic bodies resembling “copper pennies” ( Figure 2 ), features consistent with chromoblastomycosis, a cutaneous deep fungal infection. Oral terbinafine (anti-fungal sterol inhibitor) was administered at 250 mg two times daily for 2 weeks and then, 250 mg daily for 14 weeks, with progressive resolution. Chromoblastomycosis, caused by a saprophytic pigmented (dematiaceous) fungus, occurs in many tropical areas, including Thailand. 1 It may be acquired by traumatic implantation, such as a wood splinter contaminated with fungal elements. Regional lymphatic damage and malignant transformation may occur. Treatment options include oral anti-fungal medications and physical methods, the former often requiring lengthy courses, and responses vary. 1, 2 Here, we speculate that terbinafine dosed at 500 mg daily for the first 2 weeks, a less commonly prescribed higher daily dose, may have been beneficial.