Tinea nigra

This code represents Tinea nigra, a superficial fungal infection of the stratum corneum, typically presenting as a solitary, irregular, hyperpigmented macule or patch. It is caused by Hortaea werneckii (formerly Exophiala werneckii) and most commonly affects the palms and soles, mimicking melanocytic lesions.

Use this code when documentation confirms a diagnosis of Tinea nigra, often based on clinical appearance and confirmed by microscopic examination (e.g., KOH preparation showing septate hyphae and budding cells). This code is appropriate for initial diagnosis and subsequent encounters related to the management of this specific fungal infection.

• Differentiate from other hyperpigmented lesions like nevi or melanoma, which require different coding.
• Ensure documentation specifies "Tinea nigra" to support this precise code.
• Do not confuse with other tinea infections (e.g., tinea pedis, tinea manuum) which have distinct ICD-9-CM codes.