Question

What is the patina formed on copper pennies?

Answer 1

A 45-year-old male agriculturist presented to the dermatology outpatient clinic with asymptomatic slowly progressive exophytic lesions over the left lower limb since 4 years. Examination revealed multiple verrucous plaques and nodules with scaling and a few black dots on the surface of some lesions [Figure 1]. He gave a history of trauma a few years back while farming, preceding the onset of lesions.



Figure 1

Chromoblastomycosis showing multiple verrucous plaques and nodules with scaling and a few black dots

Skin scraping with 10% potassium hydroxide (KOH)–a simple office diagnostic procedure–was performed, which showed multiple round thick-walled brownish budding bodies resembling copper pennies (also known as sclerotic/muriform/medlar bodies) [Figure 2]. Later, histopathologic examination demonstrated similar pigmented sclerotic bodies within epithelioid granulomas, within Langhans giant cells and also in intra- and subepidermal abscesses, thus confirming the diagnosis of chromoblastomycosis. Tissue fungal culture grew Fonsecaea pedrosoi, and was identified as the etiological agent.



Figure 2

Skin scraping showing classical golden brown septate “copper pennies” on 10% KOH mount

Chromoblastomycosis, a subcutaneous mycoses is caused by dematiaceous fungi such asPhialophora verrucosa, F. pedrosoi,Fonsacea compacta, andCladosporium carrionii. These fungi have been isolated from wood and soil, and the infection usually results from trauma. Male agricultural workers from rural areas are most commonly affected.[1]

Positive KOH smears and skin biopsies are confirmatory but diagnosis can be missed cytologically or histologically due to lack of “clinical suspicion” in many cases.[2] The main treatment options include long courses of systemic antifungals preferably itraconazole or terbinafine combined with cryotherpy or local heat therapy. Potassium iodide also has been used as a cost-effective treatment option, especially in India.[3,4]

We highlight the value of KOH scraping, this simple, quick, and easy-to-perform office procedure, which enabled us to initiate treatment on the same day without the typical delay associated with biopsy and culture reports. Our patient was started on oral itraconazole 100 mg twice daily and a good response was seen in 2