Pathology/Lab Coding Alert

Drop ‘multiple step’ distinction for code selection.

Before the ink was dry on the CPT^® 2021 code books, the AMA issued an extensive Microbiology-section update that accommodates additional new codes for SARS-CoV-2 antigen tests.

Read on to get the lowdown on the new codes as well as the code revisions, deletions, and text notes that clarify coding for different antigen-detection lab methods.

Distinguish Immunoassay Antigen Detection Tests

The AMA published a CPT^® update on Oct. 6 that included new codes and editorial revisions to accommodate additional testing in response to the COVID-19 pandemic.

To clarify coding for antigen-detection immunoassay tests, including new codes for SARS-CoV-2, the CPT^® Editorial Panel revised codes in two ranges that describe “Infectious agent antigen detection by immunoassay …” — 87301-87430 and 87802-87899.

The change to 87301-87430 removes the term “multiple-step method” because “the advent of automation … that allows multiple steps to occur within the … testing equipment … has diminished the utility of characterizing immunoassays [as multiple-step or single-step methods],” according to the Oct. 6 update.

Complementing that change, the panel also revised codes in the range 87802-87899 to spell out that the term “direct optical observation” means a “visual” observation.

Key: Taken together, the revisions clarify “the proper reporting for antigen tests that are read by a machine, as compared to those which can be visually interpreted without a machine,” according to the AMA. “Use codes 87301-87451 for instrumented immunoassay tests, and 87802-87899 for visually-read immunoassay tests for infectious agent antigen detection,” says William Dettwyler, MT-AMT, president of Codus Medicus, a laboratory coding consulting firm in Salem, Ore.

Code revisions, additions: As part of the immunoassay-method clarification, the CPT^® update establishes coding for SARS-CoV-2 testing by revising child code 87426 (Infectious agent antigen detection by immunoassay technique, (eg, enzyme immunoassay [EIA], enzyme-linked immunosorbent assay [ELISA], fluorescence immunoassay [FIA], immunochemiluminometric assay [IMCA]) qualitative or semiquantitative; severe acute respiratory syndrome coronavirus (eg, SARS-CoV, SARS-CoV-2 [COVID-19])) (under parent code 87301). The update also adds a new child code, 87811 (Infectious agent antigen detection by immunoassay with direct optical (ie, visual) observation; severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Coronavirus disease [COVID-19])), under parent code 87802.

More: To accommodate the clarifications, the CPT^® update also deletes 87450, which described a “single step method,” and converts codes 87449 (… not otherwise specified, each organism) and 87451 (… polyvalent for multiple organisms, each polyvalent antiserum) to child codes under revised code 87301. These changes indicate how you should code single and multiplex tests for “not otherwise specified” infectious agents.

Clarify ‘Fluorescence’ Antigen Detection Coding

The Oct. 6 CPT^® update also includes clarification for tests that use fluorescence to detect infectious agent antigens.

Microscopic: When labs perform tests using codes in the range 87260-87300 (Infectious agent antigen detection by immunofluorescent technique …), the update adds language to the section instructions clarifying that these codes describe tests involving microscopic identification of infectious agents using direct/indirect immunofluorescent assay (IFA) techniques.

FIA: The CPT^® update revises the 87301 code family to add fluorescence immunoassay (FIA) to the list of other method examples, such as enzyme immunoassay (EIA). The section instructions point to the 87301 family for non-microscopic FIA methods that are instrumented, or the 87802 family for fluorescence methods that use visual identification.

Greet Multiplex Respiratory Antigen CPT^® Codes

As we enter the “cold and flu” season, the CPT^® Oct. 6 update includes the following two new codes for respiratory virus panels that include SARS-CoV-2:

• 87636 (Infectious agent detection by nucleic acid (DNA or RNA); severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Coronavirus disease [COVID-19]) and influenza virus types A and B, multiplex amplified probe technique)
• 87637 (… severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Coronavirus disease [COVID-19]), influenza virus types A and B, and respiratory syncytial virus, multiplex amplified probe technique)

These two newly approved codes “report nucleic acid assays that allow a single test to simultaneously detect the novel coronavirus and a combination of common viral infectious agents, including influenza A/B and respiratory syncytial virus [RSV],” said AMA President Susan R. Bailey, MD, in a release about the new codes. “Concurrent detection promises to conserve important testing resources, allowing for ongoing surveillance of influenza while testing for the novel coronavirus.”

Existing codes: CPT^® already provides Category I codes for multiple respiratory viral targets: 87631, 87632, and 87633 for 3-5 targets, 6-11 targets, and 12-25 targets, respectively (Infectious agent detection by nucleic acid (DNA or RNA); respiratory virus (eg, adenovirus, influenza virus, coronavirus, metapneumovirus, parainfluenza virus, respiratory syncytial virus, rhinovirus), includes multiplex reverse transcription, when performed, and multiplex amplified probe technique, multiple types or subtypes …). But the CPT^® Editorial panel determined that as the COVID-19 pandemic progresses, “the need to be able to distinguish the tests for influenza A, influenza B, and RSV that include SARS-CoV-2 from those that do not has become apparent.” For that specific purpose, the panel added codes 87636 and 87637, which you must use for tests that fit those specific descriptions (unless you’re using a proprietary laboratory analyses (PLA) test, which you’ll read more about in the next section).

See notes: The Oct. 6 update indicates that you must use the most specific code for your test, such as 87636 or 87637. The update also includes text notes indicating that you should reserve 86731, 86732, or 86733 for the following situations:

For nucleic acid detection of multiple respiratory infectious agents not including SARS-CoV-2

For nucleic acid detection of multiple respiratory infectious agents that include SARS-CoV-2, with additional targets beyond influenza A and B and RSV.

Don’t Miss New PLA Antigen Codes

You’ll find the following two new PLA codes, which describe lab- or manufacturer-specific respiratory panel codes that include the SARS-Cov-2 target, in the recent CPT^® update:

• 0240U (Infectious disease (viral respiratory tract infection), pathogen-specific RNA, 3 targets (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2], influenza A, influenza B), upper respiratory specimen, each pathogen reported as detected or not detected)
• 0241U (Infectious disease (viral respiratory tract infection), pathogen-specific RNA, 4 targets (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2], influenza A, influenza B, respiratory syncytial virus [RSV]), upper respiratory specimen, each pathogen reported as detected or not detected)

Both codes are “Xpert^® Xpress” tests from Cepheid, and are effective Oct. 6.

More: You won’t find the following two PLA respiratory pathogen panels in your CPT^® 2021 code book, but they’ve been effective since this past summer:

• 0223U (Infectious disease (bacterial or viral respiratory tract infection), pathogen-specific nucleic acid (DNA or RNA), 22 targets including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), qualitative RT-PCR, nasopharyngeal swab, each pathogen reported as detected or not detected) for QIAstat-Dx Respiratory SARS CoV-2 Panel from QIAGEN Sciences
• 0225U (Infectious disease (bacterial or viral respiratory tract infection) pathogen-specific DNA and RNA, 21 targets, including severe acute respiratory syndrome coronavirus 2 (SARSCoV-2), amplified probe technique, including multiplex reverse transcription for RNA targets, each analyte reported as detected or not detected) for ePlex^® Respiratory Pathogen Panel 2 from GenMark Diagnostics.