CPT® Code 87327

Infectious agent antigen detection by immunoassay technique, (eg, enzyme immunoassay [EIA], enzyme-linked immunosorbent assay [ELISA], fluorescence immunoassay [FIA], immunochemiluminometric assay [IMCA]) qualitative or semiquantitative; Cryptococcus neoformans

The CPT® Code 87327 refers to a laboratory test designed to detect the presence of the antigen associated with Cryptococcus neoformans, a pathogenic fungus that can lead to serious infections, particularly in individuals with weakened immune systems. This test employs various immunoassay techniques, including enzyme immunoassay (EIA), enzyme-linked immunosorbent assay (ELISA), fluorescence immunoassay (FIA), and immunochemiluminometric assay (IMCA). Cryptococcus neoformans is an encapsulated yeast-like fungus commonly found in the environment, and it can cause infections in multiple body systems, notably the lungs and central nervous system, especially in immunocompromised patients. To perform this test, a biological sample, such as cerebrospinal fluid, is collected and either preserved in a fixative or sent fresh to the laboratory for analysis. The immunoassay techniques utilized in this test are highly sensitive and capable of detecting minute quantities of the Cryptococcus neoformans antigen. In EIA and ELISA, the antigen binds to a specific antibody, and a secondary enzyme-labeled antibody is introduced to facilitate detection. The presence of the antigen is indicated by a chromogenic reaction that results in a visible color change or fluorescence, which can be quantitatively or qualitatively assessed through colorimetric readings. FIA, on the other hand, utilizes a fluorescent compound to detect the binding of the detection antibody to the antigen, while IMCA employs antibodies labeled with a chemiluminescent substance to identify and quantify the antigen-antibody complex through light emission. This comprehensive approach allows for accurate detection and assessment of Cryptococcus neoformans, aiding in the diagnosis and management of infections caused by this organism.