CPT® Code 87560

The CPT® Code 87560 refers to a laboratory test designed for the detection of the infectious agent Mycobacteria avium-intracellulare (MAI) through the use of nucleic acid techniques, specifically targeting DNA or RNA. Mycobacteria avium-intracellulare is part of the Mycobacteria avium complex (MAC), which consists of two species of gram-positive, acid-fast, atypical bacteria that are often indistinguishable from one another. 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 direct probe technique utilized in this test involves identifying a specific nucleic acid sequence, known as the target sequence, that is unique to the MAI organism. This detection can occur in various biological samples, including blood, tissue, cerebrospinal fluid (CSF), or synovial fluid. The probe used in this technique is labeled with either fluorescent or chemiluminescent markers, allowing for the visualization of the hybrid formed when the probe binds to the target sequence. The process includes treating the sample to release nucleic acids from the target organism, if present, and then the labeled probe specifically binds to the matching target sequence, forming a stable hybrid. Ribosomal RNA is often the focus of this detection method due to its abundance in microorganisms, as it is typically present in thousands of copies compared to the limited copies of genomic DNA. This method is distinct from the amplified probe technique, which significantly enhances assay sensitivity by exponentially amplifying the target sequence of MAI DNA or RNA, often utilizing polymerase chain reaction (PCR) or reverse transcriptase polymerase chain reaction (RT-PCR) for this purpose. The amplified sequences can then be identified using labeled DNA probes, and further quantification of these nucleic acids can provide insights into the number of microorganisms present in the sample.