ICD-10 Code B40.89 – Other forms of blastomycosis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B40.89 – Other forms of blastomycosis
What it is
B40.89 identifies blastomycosis that does not fit the more specific pulmonary, cutaneous, or disseminated categories. Use it when the record documents blastomycosis, but the site or pattern is described as other or unspecified.
Clinical signs
Clinical features vary; refer to documentation. Blastomycosis can present with fever, cough, weight loss, skin lesions, or other organ involvement, but this code is used when the chart does not support a more specific form.
When to use this code
Use B40.89 when the provider documents blastomycosis and specifies an atypical or other form that is not captured by a more specific code. It also applies when the diagnosis is confirmed but the available record does not clearly identify the affected site.
Review the note for pulmonary, cutaneous, or disseminated disease before assigning this code. If the documentation is incomplete, check documentation rather than guessing the subtype.
Do not use for
Do not use this code for blastomycosis with a clearly documented pulmonary, cutaneous, or disseminated presentation. Do not use it when another fungal infection or a different diagnosis is recorded.
Coding tip
Look for the exact wording “other forms” or similar nonspecific language in the provider note before selecting B40.89.