ICD-10 Code B40.0 – Acute pulmonary blastomycosis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B40.0 – Acute pulmonary blastomycosis
What it is
B40.0 identifies acute pulmonary blastomycosis, a fungal infection of the lungs caused by Blastomyces. Use it when the infection is newly recognized and involves the pulmonary system.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings include cough, fever, chest discomfort, and shortness of breath, with imaging that may suggest pneumonia or other pulmonary infection.
When to use this code
Use B40.0 when the provider documents acute pulmonary blastomycosis or acute lung infection due to Blastomyces. It is appropriate when the illness is limited to the lungs and no other blastomycosis site is documented. Check documentation if the record only says blastomycosis without acuity or pulmonary involvement.
Do not use for
Do not use this code for chronic, disseminated, or cutaneous blastomycosis unless the lung infection is specifically documented. Avoid it when the diagnosis is uncertain or only suspected.
Coding tip
Code the site and acuity exactly as documented; if the note is incomplete, query for confirmation before assigning B40.0.