2025 CPT code 87400
(Active) Effective Date: N/A Revision Date: N/A Infectious Agent Antigen Detection - Microbiology Procedures Pathology and Laboratory Feed
Detects influenza A or B antigens using immunoassay techniques (EIA, ELISA, FIA, IMCA).
Modifiers 59 (distinct procedural service), 91 (repeat clinical diagnostic lab test), and QW (CLIA waived test) may be applicable depending on the specific circumstances.
Medical necessity is established when clinical findings suggest acute influenza infection. The test aids in diagnosis, allowing for appropriate treatment (e.g., antiviral medications) and infection control measures. Documentation should support the clinical indication for testing.
Laboratory personnel perform the technical aspects of the test, including specimen processing, running the assay, and interpreting the results. Clinicians order the test to assist in diagnosing influenza and guiding treatment decisions.
In simple words: This lab test checks for flu viruses (type A or B) in a sample from your body (like blood, mucus, or a nasal swab). It uses special techniques to find out if you have the flu and which type you have. The results can help your doctor determine the best treatment.
This CPT code encompasses the qualitative or semiquantitative detection of influenza A or B virus antigens in a patient specimen using immunoassay techniques such as enzyme immunoassay (EIA), enzyme-linked immunosorbent assay (ELISA), fluorescence immunoassay (FIA), or immunochemiluminometric assay (IMCA).The test differentiates between influenza A and B. Specimens may include serum, sputum, nasal swabs, or throat swabs.The code is reported once for each influenza type (A or B) detected.If both A and B are tested, the code should be reported twice, potentially with modifier 59 to indicate distinct procedural services.
Example 1: A patient presents with flu-like symptoms (fever, cough, body aches).The physician orders an influenza A and B antigen test using an EIA method. The lab reports positive for influenza A, and 87400 is billed once. If influenza B was also positive,87400 would be billed twice, with modifier 59 to indicate distinct services., A patient with a compromised immune system experiences respiratory symptoms.The physician requests rapid influenza testing to guide antiviral treatment.A CLIA-waived rapid influenza A/B test is performed (e.g., BinaxNOW). Code 87400 is billed appropriately. Modifier QW may be added for CLIA-waived tests where required., A healthcare facility conducts routine influenza surveillance.Nasal swabs are collected from multiple patients.The lab performs influenza A/B testing using ELISA. Multiple specimens/sites would use modifier 59.If the same day repeat test is done, modifier 91 would be used.
Patient demographics, date of service, specimen type (e.g., nasal swab, sputum), test method used (EIA, ELISA, FIA, or IMCA), results (positive/negative for influenza A and/or B), and physician's order for the test.For CLIA waived tests, documentation should also reflect the waived status.
** The code should not be used in conjunction with molecular diagnostic codes (e.g., 81161, 81200-81408).Some payers may require separate billing for specimen collection (e.g., 36415).Always refer to payer-specific guidelines for accurate billing.
- Revenue Code: T1H (Lab Tests - Other)
- Payment Status: Active
- Specialties:Infectious Disease, Internal Medicine, Family Medicine, Pediatrics, Emergency Medicine, Laboratory Medicine
- Place of Service:Office, Hospital (Inpatient and Outpatient), Urgent Care, Clinical Laboratory