K31.6 vs K63.2
K31.6 and K63.2 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on K63.2
fistula of duodenum (K31.6)
K31.6
Fistula of stomach and duodenum
Billable
- Chapter 11
- Diseases of the digestive system
- Section
- K20-K31
Use when the record says
- Gastrocolic fistula
- Gastrojejunocolic fistula
Indexed under
- Fistula › duodenum (cutaneous)
- Fistula › gastric (cutaneous)
- Fistula › gastrocolic (cutaneous)
- Fistula › gastroenterocolic (cutaneous)
- Fistula › gastroesophageal (cutaneous)
K63.2
Fistula of intestine
Billable
- Chapter 11
- Diseases of the digestive system
- Section
- K55-K64
Indexed under
- Fistula › abdomen (cutaneous)
- Fistula › abdominorectal (cutaneous)
- Fistula › abdominosigmoidal (cutaneous)
- Fistula › cecosigmoidal (cutaneous)
- Fistula › cecum (cutaneous)
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027