Pathology/Lab Coding Alert

Don't forget the reason for the test

Guaiac-based fecal-occult blood tests (FOBT) aren't the only show in town. Labs may also perform an immunoassay FOBT, and that means using completely different codes.

One CPT code and one HCPCS Level II code describe the immunoassay test:

- 82274 -- Blood, occult, by fecal hemoglobin determination by immunoassay, qualitative, feces, 1-3 simultaneous determinations

- G0328 --Colorectal cancer screening; fecal-occult blood test, immunoassay, 1-3 simultaneous determinations.

The immunoassay, which identifies an antigen on the globin part of the molecule, is less sensitive to diet or stomach bleeding than the peroxidase test, but fecal flora may destroy the antigen.

Document Screening or Diagnostic

Medicare began covering the immunoassay test as an alternative to the guaiac-based test for FOBT screening in 2004. You should use G0328 if the ordering physician states that the immunoassay FOBT is for colorectal cancer screening or requests the test with a screening code such as V76.51 (Special screening for malignant neoplasms; colon), says Anne Pontius, MBA, CMPE, MT (ASCP), president of Laboratory Compliance Consultants Inc. in Raleigh, N.C.

Caution: Medicare will pay for a covered screening FOBT once every 12 months using either immunoassay (G0328) or guaiac (82270, Blood, occult, by peroxidase activity [e.g., guaiac], qualitative; feces, consecutive collected specimens with single determination, for colorectal neoplasm screening [i.e., patient was provided three cards or single triple card for consecutive collection]), but not both. 

For a diagnostic immunoassay FOBT that the physician orders based on patient symptoms, use 82274.

Watch for New CLIA-Waived Test

The Oct. 1 update of tests granted waived status under the Clinical Laboratory Improvement Amend-ments adds an immunoassay FOBT -- immoCare Fecal Occult Blood Test -- to the list. Labs with a certificate of waiver should use modifier QW (CLIA waived test). Report the test as 82274-QW or G0328-QW, depending on whether it is a diagnostic or screening test.