Pathology/Lab Coding Alert

Question: When billing for infectious agent tests such as Chlamydia (87491) and gonorrhea (87591), can we separately bill 83891 for the specimen preparation using nucleic acid extraction techniques?

Texas Subscriber

Answer: No, you should not bill 83891 (Molecular diagnostics; isolation or extraction of highly purified nucleic acid) in addition to 87491 (Infectious agent detection by nucleic acid [DNA or RNA]; Chlamydia trachomatis, amplified probe technique) or 87591 (- Neisseria gonorrhoeae, amplified probe technique).

CPT contains nearly 140 codes for infectious agent detection from primary-source specimens using various lab methods. Ranging from 87260 (Infectious agent antigen detection by immunofluorescent technique; adenovirus) to 87899 (Infectious agent detection by immunoassay with direct optical observation; not otherwise specified), these codes describe the entire test, from specimen preparation through organism identification. You should not separately report individual steps that the lab performs to complete the identification. Rather, you should select the single most specific code that describes both the lab method used and the organism identified.

Don't double-dip: Some of the steps that labs use for infectious-agent detection by nucleic acid are similar to the procedures described by the molecular diagnostics codes (83890-83913). These include processes such as nucleic acid extraction (83891) and amplification (83898, Molecular diagnostics; amplification, target, each nucleic acid sequence). The molecular diagnostic codes correctly describe these step-wise lab procedures for genetic studies.

Coders might think they can report these molecular steps along with the infectious agent detection code, but that is incorrect and amounts to unbundling. That's why CMS- Correct Coding Initiative (CCI) bundles each code for infectious agent detection by nucleic acid with each of the molecular diagnostics codes (83890-83913). That includes edit pairs for 87491 and 87591 with 83891 -- the codes you asked about.