Pathology/Lab Coding Alert

Reverse transcription not required.

Now that you’ve refreshed your memory on how to code infectious agent antigen detection, make sure you understand the one little change in CPT® 2014 that affects seven of those codes — and could affect your bottom line.

Clarify Amplified Probe Codes

If you bill for infectious agent antigen detection by amplified probe technique, also called nucleic acid amplification test (NAAT), here’s something you need to know.

Problem: CPT® 2013 changed the description of several infectious agent antigen detection codes from “amplified probe technique” to “reverse transcription and amplified probe technique.” That left coders in a dilemma: You had no way to accurately report a test that used amplified probe technique but didn’t involve reverse transcription.

“While reverse transcription is a necessary component of a NAAT using polymerase chain reaction (PCR) for an RNA target, there are other NAATs that do not use PCR, thus the step is not always relevant,” explains Vickie Baselski, PhD, D(ABMM), F(AAM), professor of pathology and laboratory medicine at the University of Tennessee Health Science Center in Memphis.

CPT® 2014 changes the code definitions to state, “amplified probe technique, includes reverse transcription when performed.” That means the code includes reverse transcription, if performed, but the reverse transcription step isn’t necessary to use the codes.

Problem solved: “I believe that in order to simplify coding, and price all NAATs into the same reimbursement category since organism-specific data are used essentially identically in patient management, the AMA elected to revise the wording for amplified probes to be inclusive of the reverse transcription step if required,” Baselski says.

Here are the revised 2014 codes:

• 87498 — Infectious agent detection by nucleic acid (DNA or RNA); enterovirus, amplified probe technique, includes reverse transcription when performed
• 87521 — ... hepatitis C, amplified probe technique, includes reverse transcription when performed
• 87522 — ... hepatitis C, quantification, includes reverse transcription when performed
• 87535 — ... HIV-1, amplified probe technique, includes reverse transcription when performed
• 87536 — ... HIV-1, quantification, includes reverse transcription when performed
• 87538 — ... HIV-2, amplified probe technique, includes reverse transcription when performed
• 87539 — ... HIV-2, quantification, includes reverse transcription when performed.

Capture Trich Test

CPT® 2014 has one new code in the microbiology section: 87661 (Infectious agent detection by nucleic acid (DNA or RNA); Trichomonas vaginalis, amplified probe technique).

Use this code for an amplified probe test to detect Trichomonas vaginalis, a protozoan parasite. This is an organism that may cause vaginitis or urogenital infection, according to Kimberly Walker, representing the American Society for Microbiology at the CMS annual Clinical Laboratory Fee Schedule (CLFS) public meeting.

Although CPT® provides other method-specific tests for Trichomonas vaginalis, such as 87808 (Infectious agent antigen detection by immunoassay with direct optical observation; Trichomonas vaginalis) and 87660 (Infectious agent detection by nucleic acid (DNA or RNA); Trichomonas vaginalis, direct probe technique), you shouldn’t use those codes for an amplified probe technique test for the organism.

“Coders may have reported this test with the general methodology code 87798 (Infectious agent detection by nucleic acid [DNA or RNA], not otherwise specified; amplified probe technique, each organism) prior to the addition of 87661,” says William Dettwyler, MT AMT, president of Codus Medicus, a laboratory coding consulting firm in Salem, Ore.