Q: How should we code a diagnosis of influenza type A? Should we report ICD-9-CM code 487.1?
A: The correct ICD-9-CM code for a patient who has influenza with respiratory manifestations is 487.1. No other code is necessary because 487.1 includes manifestations of laryngitis, pharyngitis, or respiratory infection (upper) (acute).
However, when a physician documents influenza type A, coders should query to determine whether the patient has one of the following conditions:
Influenza due to identified avian influenza virus, which includes avian influenza, bird flu, and influenza A/H5N1 (ICD-9-CM code 488.0)
Influenza due to identified novel H1N1 influenza virus, which includes 2009 H1N1 (swine) influenza virus, novel 2009 influenza H1N1, novel H1N1 influenza, novel influenza A/H1N1, or swine flu (ICD-9-CM code 488.1)
Neither 488.0 nor 488.1 require an additional code.
Editor’s note: Sandra Sillman, RHIT, PAHM, DRG coordinator at Henry Ford Health System in Detroit, answered this question in the January issue of Briefings on Coding Compliance.