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The CPT® Code 87542 refers to a laboratory test designed for the detection of the infectious agent Legionella pneumophila through the analysis of nucleic acids, specifically DNA or RNA. Legionella pneumophila is a gram-negative bacterium commonly found in aquatic environments, which can lead to serious health issues such as pneumonia, known as Legionnaire’s Disease, or a milder illness resembling influenza, referred to as Pontiac Fever. This test utilizes a direct probe method to identify a unique nucleic acid sequence, termed the target sequence, associated with the L. pneumophila organism, should it be present in a respiratory specimen. The detection process involves the use of a probe that is labeled with either fluorescent or chemiluminescent markers. To perform the test, the sample is treated to release nucleic acids from the target organism, if it exists. The labeled probe then selectively 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 typically exists in thousands of copies compared to the limited 1-2 copies found in genomic DNA. The sensitivity of the assay is significantly enhanced through an amplified probe technique, which involves exponentially multiplying the target sequence of L. pneumophila DNA or RNA into millions of copies. The polymerase chain reaction (PCR) or reverse transcriptase polymerase chain reaction (RT-PCR) is the most frequently employed amplification technique. Following amplification, the replicated sequences are identified using labeled DNA probes. The quantification aspect of this test, as indicated by the CPT® Code 87542, provides a measurement of the number of microorganisms present in the sample. Quantitative or real-time PCR is typically utilized to amplify the isolated nucleic acid segment and generate a report that documents the absolute or relative amounts of the known nucleic acid sequence at each stage of the testing process.
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The CPT® Code 87542 is indicated for the detection and quantification of the infectious agent Legionella pneumophila in respiratory specimens. This test is particularly relevant for patients presenting with symptoms consistent with pneumonia or influenza-like illnesses, where the presence of L. pneumophila may be suspected. The following conditions may warrant the use of this test:
The procedure for CPT® Code 87542 involves several critical steps to ensure accurate detection and quantification of Legionella pneumophila. The following procedural steps are outlined:
After the completion of the procedure associated with CPT® Code 87542, the laboratory will analyze the results and generate a report detailing the presence and quantity of Legionella pneumophila in the sample. Clinicians will review these results to inform diagnosis and treatment decisions. It is important for healthcare providers to consider the clinical context and symptoms of the patient when interpreting the results. Follow-up care may include additional testing or treatment based on the findings, and patients may be monitored for any progression of symptoms or complications related to the detected infection.
| Short Descr | LEGION PNEUMO DNA QUANT | Medium Descr | IADNA LEGIONELLA PNEUMOPHILA QUANTIFICATION | Long Descr | Infectious agent detection by nucleic acid (DNA or RNA); Legionella pneumophila, quantification | Status Code | Statutory Exclusion (from MPFS, may be paid under other methodologies) | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 9 - Not Applicable | Multiple Procedures (51) | 9 - Concept does not apply. | Bilateral Surgery (50) | 9 - Concept does not apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 9 - Concept does not apply. | Co-Surgeons (62) | 9 - Concept does not apply. | Team Surgery (66) | 9 - Concept does not apply. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | CLIA Waived (QW) | No | APC Status Indicator | Conditionally packaged laboratory tests | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | T1H - Lab tests - other (non-Medicare fee schedule) | MUE | 1 | CCS Clinical Classification | 206 - Microscopic examination (bacterial smear, culture, toxicology) |
| 90 | Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number. | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | GW | Service not related to the hospice patient's terminal condition | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service |
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| 2011-01-01 | Changed | Short description changed. |
| 1998-01-01 | Added | First appearance in code book in 1998. |
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