Question: We are very confused about how to code for influenza tests. When billing Medicaid or Tricare, we were advised to bill 87804, even though we are accustomed to reporting 87502 instead. In addition, if we bill two types of flu tests, we typically report 87502 followed by a unit of 87502-59, but the doctors are saying to report two units of the flu test code instead of using modifier 59. Can you advise?
Answer: Most pediatric offices will not report 87502 (Infectious agent detection by nucleic acid (DNA or RNA); influenza virus, for multiple types or sub-types, includes multiplex reverse transcription, when performed, and multiplex amplified probe technique, first 2 types or sub-types) at all. This is a waived lab test as of January 2015, but it would be rare for a pediatric practice to use this type of flu test.
Instead, most pediatric practices will report 87804 (Infectious agent antigen detection by immunoassay with direct optical observation; Influenza), which is a more commonly performed service in outpatient practices. If you perform the test for both strains of the flu, you will typically report 87804 twice. Many carriers allow you to report 87804 x 2 without a problem, because the MUEs (medically unlikely edits) that Medicaid and some other payers utilize to auto-deny second and subsequent line items limits you to two units of 87804. This means that your carrier will process two units of the code but would most likely auto-deny three or more units billed together.
For payers that do not recognize two units of 87804 and deny the second charge as a duplicate, use modifier 59 (Distinct procedural service) on the second 87804 entry. This modifier indicates that a different test was performed to test for a distinct strain.