ICDcodes.org
FY2027

K52.3 vs K52.9

K52.3 and K52.9 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 K52.3
unspecified colitis (K52.9)
K52.3

Indeterminate colitis

Billable
Chapter 11
Diseases of the digestive system
Section
K50-K52
Use when the record says
  • Colonic inflammatory bowel disease unclassified (IBDU)
Indexed under
  • IBDU (colonic inflammatory bowel dissease unclassified)
  • Colitis › indeterminate, so stated (acute) (catarrhal) (chronic) (noninfective) (hemorrhagic)
  • Disease, diseased › colonic inflammatory bowel, unclassified
K52.9

Noninfective gastroenteritis and colitis, unspecified

BillableUnspecified
Chapter 11
Diseases of the digestive system
Section
K50-K52
Use when the record says
  • Colitis NOS
  • Enteritis NOS
  • Gastroenteritis NOS
  • Ileitis NOS
  • Jejunitis NOS
  • Sigmoiditis NOS
Indexed under
  • Cecitis
  • Colitis (acute) (catarrhal) (chronic) (noninfective) (hemorrhagic)
  • Enteritis (acute) (diarrheal) (hemorrhagic) (noninfective)
  • Enterocolitis
  • Gastroenteritis (acute) (chronic) (noninfectious)

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