General Surgery Coding Alert

Answer: No, you should not code this as a diagnostic colonoscopy in this case, assuming you have documentation that the ordering physician requested a medically-appropriate screening colonoscopy.

Here’s why: During a screening procedure, the surgeon should document incidental findings and you should code any appropriate diagnosis. But if the findings don’t change the fundamental nature of the procedure, you should not change the procedure code. In addition to hemorrhoids, incidental colonoscopy findings might include diverticulosis or anal fissures. You should report those as a secondary diagnoses following the ordering diagnosis of Z12.11 (Encounter for screening for malignant neoplasm of colon) as the primary code.

Do this: Report the procedure as G0105 (Colorectal cancer screening; colonoscopy on individual at high risk) or G0121 (… colonoscopy on individual not meeting criteria for high risk) for Medicare patients. For non-Medicare patients, the appropriate code is 45378 (Colonoscopy, flexible; diagnostic, including collection of specimen(s) by brushing or washing, when performed (separate procedure)).

If the surgeon does indeed convert the screening to a diagnostic procedure, by taking a biopsy or removing a polyp for instance, then you should report the appropriate diagnostic colonoscopy code with an appropriate modifier. To indicate that the procedure was a screening colonoscopy that the surgeon converted to diagnostic, you might append modifier 33 (Preventive Services) or PT (Colorectal cancer screening test; converted to diagnostic test or other procedure) to procedure code 45380 (Colonoscopy, flexible; with biopsy, single or multiple) for non-Medicare and Medicare payers, respectively.

Why it matters: When a screening becomes diagnostic (when the surgeon finds and removes a polyp, for instance), federal regulations dictate that payers (with a Medicare phase in) waive the deductible and copay costs.