ICD-10 Code B40.1 – Chronic pulmonary blastomycosis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B40.1 – Chronic pulmonary blastomycosis
What it is
B40.1 identifies chronic pulmonary blastomycosis, a long-lasting fungal infection affecting the lungs. Use it when documentation specifies chronic pulmonary disease caused by Blastomyces.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings include persistent cough, chest discomfort, shortness of breath, and imaging changes consistent with chronic pulmonary infection.
When to use this code
Use B40.1 when the provider documents chronic blastomycosis limited to the lungs. It may also fit when records describe chronic pulmonary blastomycosis, pulmonary blastomycotic infection, or chronic lung involvement from Blastomyces. Check documentation if the site or chronicity is unclear.
Do not use for
Do not use this code for acute or unspecified blastomycosis, or for nonpulmonary involvement. If the record does not confirm chronic pulmonary disease, check documentation.
Coding tip
Confirm both the chronic nature and the pulmonary site before assigning B40.1.