Question: I thought I had to wait for the test result before coding a flu diagnosis, but just heard otherwise. Am I misunderstanding something? Florida Subscriber Answer: Flu coding comes with a few different rules, which is why your question is a common one. If a patient experiences fever, muscle pain, sore throat, earache, cough, and runny nose, and the provider documents suspicion of influenza with otitis media, reporting a flu diagnosis is the appropriate action. For this specific encounter, that would likely mean J11.83 (Influenza due to unidentified influenza virus with otitis media). Here’s why this is tricky: Usually when the provider suspects a diagnosis before its confirmed, you have probably followed ICD-10-CM Official Guidelines, Section IV.H, which tells you not to “code diagnoses documented as ‘probable,’ ‘suspected,’ ‘questionable,’ ‘rule out,’ ‘compatible with,’ ‘consistent with,’ or ‘working diagnosis’ or other similar terms indicating uncertainty” when coding and reporting diagnoses in outpatient settings. However, flu coding overrides that rule in favor of the doctor’s clinical judgment. Take a look at guideline I.C.10.c. Instructions do say to “code only confirmed cases of influenza.” However, the guideline goes on to say that confirmation “does not require documentation of positive laboratory testing specific for avian or other novel influenza A or other identified influenza virus.” The guideline then explains that “coding should be based on the provider’s diagnostic statement” for J09.- (Influenza due to certain identified influenza viruses) if your provider documents that “the patient has avian influenza, or other novel influenza A,” or J10.- (Influenza due to other identified influenza virus) if the patient “has another particular identified strain of influenza, such as H1N1 or H3N2, but not identified as novel or variant.” And for cases of influenza recorded by the provider as “‘suspected,’ ‘possible,’ or ‘probable’ avian influenza, or novel influenza, or other identified influenza,” ICD-10 guideline I.C.10.c instructs you to assign an appropriate influenza code from category J11.- (Influenza due to unidentified influenza virus).