ICDcodes.org
FY2027

K51 vs K63.3

K51 and K63.3 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 K63.3
ulcerative colitis (K51.-)
K51

Ulcerative colitis

Not billable
Chapter 11
Diseases of the digestive system
Section
K50-K52
K63.3

Ulcer of intestine

Billable
Chapter 11
Diseases of the digestive system
Section
K55-K64
Use when the record says
  • Primary ulcer of small intestine
Indexed under
  • Stercoraceous, stercoral ulcer
  • Erosion › intestine
  • Ulcer, ulcerated, ulcerating, ulceration, ulcerative › intestine, intestinal
  • Ulcer, ulcerated, ulcerating, ulceration, ulcerative › primary of intestine
  • Ulcer, ulcerated, ulcerating, ulceration, ulcerative › rectosigmoid

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