ICD-10 Code A37.81 – Whooping cough due to other Bordetella species with pneumonia (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A37.81 – Whooping cough due to other Bordetella species with pneumonia
What it is
This code identifies pertussis caused by Bordetella species other than B. pertussis, with pneumonia documented as part of the illness. Use it when the record clearly links the whooping cough infection to pneumonia.
Clinical signs
Clinical features vary; refer to documentation. Typical findings may include paroxysmal cough, inspiratory whoop, posttussive vomiting, and evidence of pneumonia noted by the provider.
When to use this code
Use A37.81 when the clinician documents whooping cough due to another Bordetella species and also states pneumonia. This supports cases where the respiratory infection is specifically identified as pertussis with pulmonary involvement. If the organism or pneumonia is not clearly documented, check documentation before assigning the code.
Do not use for
Do not use this code for uncomplicated whooping cough without pneumonia, or for pertussis due to B. pertussis when a different code applies. Do not guess the organism or complication.
Coding tip
Code only when both the Bordetella species and pneumonia are documented together; otherwise, verify the record first.