ICD-10 Code A37.90 – Whooping cough, unspecified species without pneumonia (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A37.90 – Whooping cough, unspecified species without pneumonia
What it is
A37.90 identifies whooping cough when the Bordetella species is not specified and pneumonia is not documented. Use it for a confirmed pertussis diagnosis without a more specific organism or complication.
Clinical signs
Typical findings include paroxysmal coughing spells, inspiratory whoop, posttussive vomiting, or apnea in infants. Clinical features vary; refer to documentation.
When to use this code
Use A37.90 when the record clearly states whooping cough or pertussis, but the species is not identified. Apply it when the provider documents no pneumonia and no more specific pertussis code is available. Check documentation if the note only says “cough” or “suspected pertussis.”
Do not use for
Do not use this code for pertussis with pneumonia, which requires a different code. Do not assign it for nonspecific cough or when whooping cough is only ruled out.
Coding tip
Confirm both “whooping cough” and “without pneumonia” in the provider’s documentation before selecting A37.90.