CPT 87798 is used to detect the presence of an infectious agent in a specimen using amplified nucleic acid techniques and nucleic acid probes that bind to and identify specific sequences associated with the agent.
What Is CPT Code 87798?
CPT code 87798 is used to detect the presence of an infectious agent using amplified nucleic acid techniques and nucleic acid probes.
The lab analyst processes the specimen and amplifies specific nucleic acid sequences using polymerase chain reaction (PCR) methods.
The amplified nucleic acid is then assessed for the presence of an infectious agent using a nucleic acid probe, a single strand of DNA or RNA that binds to complementary sequences in the specimen.
The presence of the infectious agent is indicated by the presence of a labeled hybridization product that is visible to the lab analyst.”
The CPT book describes CPT code 87798 as: “Infectious agent detection by nucleic acid (DNA or RNA), not otherwise specified; amplified probe technique, each organism.”
The lab analyst processes the specimen from a direct source such as blood and performs amplification techniques, such as polymerase chain reaction (PCR), resulting in a millionfold increase in copies of a specific target nucleic acid sequence.
The lab analyst then assesses the presence of the amplified nucleic acid sequences that indicate the presence of an infectious agent not specified in another code using a nucleic acid probe, which is a fabricated single-strand sequence of DNA or RNA used to join with the complementary sequence in the specimen through a process called hybridization.
The nucleic acid probe includes a label, such as a radioactive or chemical tag, that allows the lab analyst to visualize the hybridization product.
How To Use CPT 87798
Although not limited to testing for a specific condition, providers may order CPT 87798 if they are looking for a rare cause of an infection, perhaps if testing for all the usual organisms has been reported as negative.
For example, Vibrio metschnikovii is a rare cause of wound infections after surgery. Therefore, use CPT code 87798 if the clinician orders Vibrio metschnikovii detection by nucleic acid, amplified probe technique.
If you are testing for more than one NOS organism, you may have to use a modifier such as 59, Distinct procedural service, to indicate that the lab performed multiple tests.