Inpatient Facility Coding & Compliance Alert

Question: One of our physicians performed a colonoscopy on a Medicare patient with ulcerative colitis (no biopsies taken). The report states, “Chromoendoscopy was performed using methylene blue.” What is the procedure? Is there another CPT® code besides 45378 that I can use?

Pennsylvania Subscriber

Answer: Chromoendoscopy, also called chromoscopy, is a procedure involving the topical application of stains or dyes at the time of endoscopy to enhance tissue characterization, differentiation, or diagnosis. Sometimes, chromoendoscopy is confused with endoscopic tattooing, which involves the injection of a long-lasting pigment such as India ink into the tissue for future localization. 

In chromoendoscopy, methylene blue is used to stain cells in the small bowel, colon, and intestinal metaplasia. Chromoendoscopy has no procedure code associated with it. When completed along with a colonoscopy, the chromoendoscopy may be considered incidental to the procedure, since it is only a topical application. You may use the procedure code 44799 (Unlisted procedure; intestine). You should submit documentation along with the claim as well as have your provider draft a letter of medical necessity to fully explain the procedure and why it was needed.