CPT® Code 87561

The CPT® Code 87561 refers to a laboratory test designed for the detection of the infectious agent Mycobacteria avium-intracellulare (MAI) through the use of nucleic acid amplification techniques. MAI consists of two species of gram-positive, acid-fast, atypical bacteria that are collectively known as the Mycobacteria avium complex (MAC). These bacteria are commonly found in environmental sources such as water and soil, and they can also be carried by birds and farm animals. Infections caused by MAI primarily affect the lungs, leading to a range of symptoms that may include a productive cough with significant sputum production, fever, weight loss, fatigue, and night sweats. The test utilizes an amplified probe technique to identify the unique nucleic acid sequences associated with the MAI organism. This is achieved by analyzing samples from various bodily fluids, including blood, tissue, cerebrospinal fluid (CSF), or synovial fluid. The process begins with the extraction of nucleic acids from the target organism, if present in the sample. A labeled probe, which may be fluorescent or chemiluminescent, is then introduced to the sample. This probe specifically binds to the target sequence of the MAI organism, forming a stable hybrid. In the amplified probe technique, the sensitivity of the assay is significantly enhanced by exponentially amplifying the target sequence of MAI DNA or RNA, resulting in millions of copies. The most prevalent amplification methods employed are polymerase chain reaction (PCR) and reverse transcriptase polymerase chain reaction (RT-PCR). Following amplification, the replicated sequences are identified using labeled DNA probes. Additionally, nucleic acid detection with quantification can be performed to assess the quantity of microorganisms present in the sample, often utilizing quantitative or real-time PCR to provide detailed reports on the absolute or relative amounts of the nucleic acid sequences detected.