ICD-10 Code B43 – Chromomycosis and pheomycotic abscess (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B43 – Chromomycosis and pheomycotic abscess
What it is
B43 identifies chromomycosis, a chronic fungal infection of the skin and subcutaneous tissue, including pheomycotic abscess. Use it when documentation names this specific diagnosis. Check documentation.
Clinical signs
Typical findings include slowly enlarging skin lesions, verrucous plaques, nodules, or draining abscesses, often after traumatic implantation. Clinical features vary; refer to documentation.
When to use this code
Use B43 when the provider documents chromomycosis, chromoblastomycosis, or pheomycotic abscess as the confirmed diagnosis. It may also fit chronic localized fungal skin infection with compatible pathology or culture results if the note clearly supports it.
Code the documented condition rather than a nonspecific skin infection. If the record only says “fungal lesion” or the organism is unspecified, Check documentation.
Do not use for
Do not use B43 for superficial dermatophyte infections, candidiasis, or other fungal diseases not described as chromomycosis or pheomycotic abscess. Do not assign it from appearance alone.
Coding tip
Look for the exact fungal diagnosis in the assessment, pathology, or infectious disease note before assigning B43.