CPT code 87493: C. difficile test, toxin-gene amplification2026 Medicare lab fee · Clinical Laboratory Fee Schedule
Amplified-probe nucleic-acid testing detects C. difficile toxin genes in stool when clinicians evaluate suspected C. difficile infection.
Medicare pays $37.27 for 87493 under the 2026 Clinical Laboratory Fee Schedule: one national amount, the same in every state and setting.
Medicare lab fee · CLFS 2026 Q4
National CLFS amount
$37.27
In effect since Jan 1, 2026. The same amount in every state, payment locality and setting.
- Geographic adjustment
- None
- Office vs facility
- Same
- Since 2020
- Unchanged
- CMS updates
- Quarterly
Medicare pays the lesser of the lab’s charge and this amount. Patients usually owe no Part B deductible or coinsurance for covered clinical lab tests.
On this page 8 sections
What 87493 covers
This molecular laboratory test detects C. difficile toxin-gene nucleic acid using an amplified probe. It is commonly performed on stool when evaluating diarrhea, including suspected antibiotic-associated or healthcare-associated C. difficile infection. Clinical laboratories perform the assay. A positive result identifies toxin-gene material; it does not establish that toxin is being produced or, by itself, establish active infection.
Report 87493 for the targeted C. difficile molecular assay, generally once for each specimen tested. A broader gastrointestinal pathogen panel is reported with its applicable panel code when that is the assay performed. Medicare pays 87493 only through the CLFS. The 2026 national CLFS amount is $37.27, the same across states and localities with no office or facility adjustment; it has remained unchanged since 2020. The physician fee schedule excludes the test by statute.
This summary was written with AI assistance from CMS Clinical Laboratory Fee Schedule data. Amounts on this page come directly from CMS files.
How Medicare pays 87493
Clinical lab tests aren’t priced like physician services. They’re paid from their own fee schedule, with its own rules. See the whole lab fee schedule.
One national amount
CMS sets a single Clinical Laboratory Fee Schedule amount for 87493. There’s no geographic (GPCI) adjustment, so it pays the same in every state and payment locality.
No office or facility rate
Lab tests aren’t built from relative value units, so there’s no office and facility split: the place of service doesn’t change the CLFS amount.
Updated every quarter
CMS republishes the CLFS each quarter. New tests, often proprietary laboratory analyses (PLA codes), join during the year; existing amounts are updated each January.
Excluded from the physician fee schedule
The physician fee schedule lists 87493 with status X (excluded by statute), so the test itself is paid only from the CLFS.
87493 on the lab fee schedule since 2020
87493 · CLFS 2026 Q4 (current)
$37.27
Unchanged since Jan 1, 2020
27 quarterly CLFS releases on file, first CLFS 2020 Q1. A code missing from a quarter wasn’t on that release.
87493 compared with similar tests
- 87324C. difficile toxin testStool toxin immunoassay$11.98
- Choose 87493 for amplified-probe detection of C. difficile toxin genes; 87324 is a toxin antigen immunoassay.
- 87505GI pathogen panelThree to five targets$128.29
- 87505 reports a multiplex gastrointestinal pathogen panel with 3–5 targets, rather than a targeted C. difficile molecular assay.
- 87506GI pathogen panel6–11 targets$262.99
- 87506 reports a multiplex gastrointestinal pathogen panel with 6–11 targets; 87493 is for targeted C. difficile testing.
- 87507GI pathogen panel12–25 targets$416.78
- 87507 reports a multiplex gastrointestinal pathogen panel with 12–25 targets; use 87493 for the targeted assay instead.
87493 billing questions
How does 87493 differ from a C. difficile toxin test?
87493 detects toxin-gene nucleic acid by an amplified probe. Code 87324 is used for a C. difficile toxin antigen immunoassay, so select the code matching the method performed.
Can 87493 be reported for a gastrointestinal pathogen panel?
Use the applicable gastrointestinal pathogen panel code when the laboratory performs a multiplex panel. The panel code depends on its target count; 87493 describes a targeted C. difficile assay.
How many units are generally reported?
Generally report one unit for each specimen tested with the targeted assay.
Does Medicare pay a separate interpretation under modifier 26?
Medicare pays 87493 through the CLFS only. The physician fee schedule excludes the test by statute.
What clinical context commonly prompts this test?
Clinicians commonly order it for a patient with diarrhea when considering C. difficile infection, including after antibiotic exposure or in a healthcare setting.
Where this amount comes from
FeeBase reads lab amounts directly from the CMS Clinical Laboratory Fee Schedule file for the quarter: one row per code, with its payment indicator and national amount. Contractor-priced tests are labeled, never given a made-up amount. Amounts are Medicare payment limits, not a patient’s bill or a commercial rate.
CMS CLFS 2026 Q4 · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file line behind this amount
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