ICD-10 Code J12.3 – Human metapneumovirus pneumonia (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J12.3 – Human metapneumovirus pneumonia
What it is
J12.3 identifies pneumonia caused by human metapneumovirus. Use it when the provider documents this viral organism as the cause of the lung infection.
Clinical signs
Clinical features vary; refer to documentation. Typical pneumonia findings may include cough, fever, shortness of breath, and imaging evidence of lung infection, with metapneumovirus confirmed or documented as the cause.
When to use this code
Use J12.3 when the record clearly states human metapneumovirus pneumonia, viral pneumonia due to human metapneumovirus, or an equivalent diagnosis. It fits inpatient, outpatient, and emergency settings when the organism is documented as the cause. If the note only says respiratory infection or bronchiolitis, check documentation before assigning this code.
Do not use for
Do not use this code for pneumonia caused by another organism or for unspecified viral pneumonia. If human metapneumovirus is documented without pneumonia, this code is not appropriate.
Coding tip
Confirm that pneumonia, not just upper or lower respiratory infection, is explicitly documented before assigning J12.3.