Primary Care Coding Alert

Question: Our physician is currently handling a probable case of H1N1. He wants me to use the old influenza codes (487.x), but I'm pretty sure there's already a new ICD-9 code out for H1N1. Am I right?

Texas Subscriber

Answer: No, ICD-9 guidelines instruct providers to use 487.x (Influenza) for probable, possible, or suspect cases of H1N1. As long as the infection is not confirmed as H1N1, then the previous influenza codes 487.x remains valid.

Rule: Coding should be based on the provider's diagnostic statement that the patient has novel H1N1 (H1N1 or swine flu) influenza. "In this context, 'confirmation' does not require documentation of positive laboratory testing specific for novel H1N1 influenza," according to the 2009 ICD-CM Official Guidelines for Coding and Reporting (www.cdc.gov/nchs/data/icd9/icdguide09.pdf).

Consider that H1N1 (488.1, Influenza due to identified novel H1N1 influenza virus) is only one of several strains of influenza A. Moreover, the majority of cases remain suspect as not all individuals are tested for H1N1. At the present time, there are no easy ways to decide which strain of influenza is responsible for an individual infection. H1N1 specimen testing is not available at or for all practices limiting the number of lab confirmed tests. Therefore, for flu-like symptoms, it is best not to speculate and use only the influenza codes.

Do this: Since influenza A and B symptoms are nearly identical to the H1N1 influenza strain, consider a diagnosis of H1N1 only when other cases have been diagnosed in the area.