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Official Description

Infectious agent detection by nucleic acid (DNA or RNA), not otherwise specified; direct probe technique, each organism

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 87797 refers to a laboratory test designed for the detection of infectious agents through the analysis of nucleic acids, specifically DNA or RNA. This procedure is categorized as "not otherwise specified" (NOS), indicating that it can be applied to a variety of infectious organisms that are not explicitly listed. Examples of such organisms include West Nile Virus, Human T-Lymphotropic Virus, Epstein Barr Virus, BK Virus, Adenovirus, Hepatitis E Virus, Parvovirus B19, and Human Herpesvirus 8. The test employs a direct probe technique, which involves identifying a unique nucleic acid sequence known as the target sequence that corresponds to the suspected infectious agent. This target sequence is sought within samples derived from blood, tissue, or other bodily fluids. To perform the test, the sample is treated to release nucleic acids from the target organism, if it is present. A labeled probe, which may utilize fluorescent or chemiluminescent markers, is then introduced to the sample. This probe is designed to bind specifically to the target sequence, forming a stable hybrid if the sequence is present. The method often targets ribosomal RNA, as it is typically found in high quantities within microorganisms, making it a reliable indicator for detection. In contrast, the amplified probe technique, represented by CPT® Code 87798, enhances the sensitivity of the assay by exponentially amplifying the target sequence of the organism's DNA or RNA, resulting in millions of copies. The polymerase chain reaction (PCR) or reverse transcriptase polymerase chain reaction (RT-PCR) is the most frequently utilized amplification method. Following amplification, the replicated sequences are identified using labeled DNA probes. Furthermore, CPT® Code 87799 pertains to nucleic acid detection that includes quantification, allowing for an assessment of the number of microorganisms present in the sample. This quantitative approach often employs real-time PCR to amplify the nucleic acid segment and generate detailed reports on the absolute or relative amounts of the identified nucleic acid sequence.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The CPT® Code 87797 is indicated for the detection of infectious agents that are not otherwise specified. This test is particularly useful in cases where a patient presents with symptoms of an infectious disease, but the specific causative organism has not been identified. The following conditions may warrant the use of this procedure:

  • West Nile Virus Detection of the virus responsible for West Nile fever, which can cause neurological disease.
  • Human T-Lymphotropic Virus Identification of this virus, which is associated with certain types of leukemia and lymphoma.
  • Epstein Barr Virus Testing for this virus, which is linked to infectious mononucleosis and various malignancies.
  • BK Virus Detection of this virus, which can lead to complications in kidney transplant patients.
  • Adenovirus Identification of adenoviruses, which can cause respiratory illness, conjunctivitis, and gastroenteritis.
  • Hepatitis E Virus Testing for this virus, which can cause liver inflammation and is often transmitted through contaminated water.
  • Parvovirus B19 Detection of this virus, which can cause fifth disease in children and complications in pregnant women.
  • Human Herpesvirus 8 Identification of this virus, which is associated with Kaposi's sarcoma and other lymphoproliferative disorders.

2. Procedure

The procedure for CPT® Code 87797 involves several critical steps to ensure accurate detection of the infectious agent. The following outlines the procedural steps:

  • Sample Collection A sample is collected from the patient, which may include blood, tissue, or other bodily fluids. This sample serves as the source for nucleic acid extraction.
  • Nucleic Acid Release The collected sample is treated to release nucleic acids from the target organism, if present. This step is essential for isolating the genetic material necessary for detection.
  • Probe Introduction A labeled probe, which may be fluorescent or chemiluminescent, is introduced to the sample. This probe is specifically designed to bind to the target nucleic acid sequence of the suspected infectious agent.
  • Hybridization If the target sequence is present, the labeled probe will hybridize with it, forming a stable complex. This hybridization is a critical indicator of the presence of the infectious agent.
  • Detection The hybridized complex is then detected using appropriate methods that visualize the labeled probe, confirming the presence of the infectious agent in the sample.

3. Post-Procedure

After the completion of the procedure associated with CPT® Code 87797, the laboratory will analyze the results to determine the presence of the infectious agent. The findings will be documented in a report, which will include details on whether the target nucleic acid sequence was detected. Depending on the results, further clinical evaluation or treatment may be necessary. It is important for healthcare providers to interpret the results in conjunction with the patient's clinical presentation and history. Follow-up testing or additional diagnostic procedures may be warranted based on the initial findings.

Short Descr DETECT AGENT NOS DNA DIR
Medium Descr IADNA NOS DIRECT PROBE TQ EACH ORGANISM
Long Descr Infectious agent detection by nucleic acid (DNA or RNA), not otherwise specified; direct probe technique, each organism
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 3
CCS Clinical Classification 206 - Microscopic examination (bacterial smear, culture, toxicology)
AQ Physician providing a service in an unlisted health professional shortage area (hpsa)
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.
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.
Q4 Service for ordering/referring physician qualifies as a service exemption
Date
Action
Notes
2011-01-01 Changed Short description changed.
2001-01-01 Changed Code description changed.
1998-01-01 Added First appearance in code book in 1998.
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