[Chromomycosis of the buttocks]

Area of Science:

• Mycology
• Dermatology
• Infectious Diseases

Background:

• Chromomycosis is a chronic fungal infection of the skin and subcutaneous tissue, typically affecting tropical and subtropical regions.
• It is caused by several species of dematiaceous fungi, most commonly Fonsecaea pedrosoi.
• The disease is characterized by slow-growing, warty lesions, often on exposed areas of the body.

Observation:

• A 63-year-old male patient presented with a 28-year-old lesion on his right buttock.
• The lesion appeared as a large, erythematous, and violaceous plaque with an atrophic center and peripheral warty nodules.
• The patient had a history of living in tropical areas of Argentina for professional reasons.

Findings:

• Histologic and mycologic examinations confirmed the diagnosis of chromomycosis.
• Fonsecaea pedrosoi was identified as the causative agent.
• The patient's clinical presentation mimicked lupus vulgaris, leading to a delayed diagnosis.

Implications:

• This case highlights the unusual presentation of chromomycosis involving the buttocks, a rare site for this infection.
• The diagnostic challenge posed by the mimicry of lupus vulgaris underscores the importance of considering chromomycosis in endemic areas.
• Successful treatment with oral and topical 5-fluorocytosine demonstrates an effective therapeutic approach for this rare manifestation.