J. Stephen Erbom, MD
Grand Rapids, Mich.
Test your coding knowledge. Determine how you would code this situation before looking at the box below for the answer.
If, as in your case, there is no definitive diagnosis, the patients signs and symptoms should be used to select the ICD-9 code. In this case, it appears that 787.91 is the most appropriate code.
When a coder is confused about what to code, always ask, What is the reason for the encounter/service? In this case, diarrhea was the reason for the colonoscopy and should be coded as such.
The Balanced Budget Act of 1997 requires that medical necessity be demonstrated for every diagnostic test in order for that test to be covered. The signs and symptoms often serve to indicate medical necessity when a more definitive diagnosis is not available.