Diagnosis of Cutaneous Chromoblastomycosis and Its Response to Amphotericin B Therapy: A Case Report

Abstract

Cutaneous chromoblastomycosis is a chronic subcutaneous fungal disease of the skin caused by Blastomyces dermatitidis, especially by Fonsecaea, Phialophora, and Cladophialophora species affecting the skin, lungs, intestines, stomach, and central nervous system. It is treated using itraconazole in mild cases and amphotericin B in severe cases. A six-year-old female child presented to the Dermatology Outpatient Department with pigmented brown to blackish tanned plaques and verrucous lesions on the face and extremities. These lesions were present for the past two and a half years and were slowly enlarging and involving other areas like the trunk. The lesions were proven on biopsy to be cutaneous blastomycosis. The patient was put on infusions of amphotericin B in a calculated pediatric dose. Her blood pressure and renal function tests were checked daily to avoid any electrolyte derangements, nephrotoxicity, and systemic infusion reactions caused by amphotericin B. Amphotericin B reduced the size of the cutaneous lesions, and treatment response was assessed on regular follow-ups. Chromoblastomycosis should be considered in the differential diagnosis to enable timely treatment and to prevent its lethal complications such as epidermoid carcinoma. Treatment should continue for two to three months until histopathology is negative to ensure complete eradication.

From diagnosis to treatment- Navigating Chromoblastomycosis

“…2 Direct KOH analysis of the lesions' crusts reveals numerous thick-walled, globose or ovoidal, darkbrown bodies that were singly or in groups. 7 Despite special fungal stains like Periodic acid schiff stain and Gomori methenamine stain being positive, haematoxylin and eosin stain is considered as gold standard for the diagnosis of CBM. 5 Differential diagnosis of CBM includes fungal infections like blastomycosis, phaeohyphomycosis, paracoccidioidomycosis, coccidioidomycosis; bacterial infections like leprosy, cutaneous tuberculosis, nocardiosis; mycobacterial infections like Mycobacterium fortuitum, M. marinum; parasitic infestations like rhinosporidiosis and leishmaniasis; non-infectious disorders like psoriasis, squamous cell carcinoma, lupus erythematous and sarcoidosis.…”