CPT® Code 87899

An infectious agent antigen detection test is a diagnostic procedure that utilizes immunoassay techniques combined with direct optical observation to identify the presence of specific infectious organisms in a specimen sample. This test is categorized under CPT® Code 87899, which is designated for cases where there is no specific code available for the infectious agent being tested. The procedure typically employs a rapid test kit, and the exact methodology may vary depending on the manufacturer and the specific infectious agent in question. Generally, the process begins with the collection of a sample, which may include swabs or aspirates from the patient. The sample is then treated with various reagents that facilitate the extraction of the antigen from the infectious agent. The initial step involves adding a reagent to a tube containing the sample to extract the antigen. Following this, a swab, dipstick, or test strip is introduced into the solution, which may require incubation to allow for proper interaction. A second reagent is often added to the mixture to enhance the reaction. After this step, the swab, dipstick, or strip is removed, and a third reagent may be introduced, or the sample may be transferred to a test cassette or device designed for the assay. The presence of the antigen in the sample is indicated by a color change in the test line or spot, which signifies a positive result, alongside a control line or spot that confirms the test's validity. This procedure is crucial for the rapid identification of infectious agents, aiding in timely diagnosis and treatment decisions.