[Tinea nigra: a allochthonous case report in Chile]

Area of Science:

• Dermatology
• Mycology
• Infectious Diseases

Background:

• Tinea nigra is a superficial fungal infection caused by Hortaea werneckii, typically affecting palms and soles.
• It is an infrequent, asymptomatic infection predominantly observed in tropical regions.
• Previously, no cases of tinea nigra had been documented in Chile.

Observation:

• A Chilean woman presented with asymptomatic, brown macules on both soles following international travel.
• The clinical presentation was consistent with tinea nigra, a condition not previously reported in the region.
• Diagnosis was confirmed through direct microscopic examination and mycological culture.

Findings:

• The case represents the first documented instance of tinea nigra in Chile.
• Microscopic examination and fungal culture confirmed Hortaea werneckii as the causative agent.
• The patient exhibited a favorable response to oral itraconazole treatment.

Implications:

• This report expands the known geographical distribution of tinea nigra.
• It highlights the importance of considering tinea nigra in differential diagnoses for palmar and plantar hyperpigmentation, even in non-tropical regions.
• Early diagnosis and treatment with antifungal agents like itraconazole are effective for managing tinea nigra.