ICD-10-CM 2027
ICD-10 code for ulcerative chronic colitis
Ulcerative colitis, unspecified, without complications
From the official ICD-10-CM alphabetic index entry “Colitis (acute) (catarrhal) (chronic) (noninfective) (hemorrhagic) › ulcerative (chronic)”. Page updated September 29, 2026.
About coding ulcerative chronic colitis
The ICD-10-CM code for ulcerative chronic colitis is K51.90 (Ulcerative colitis, unspecified, without complications). The official index lists 14 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on K51.90.
Within K51.9, choose K51.90 (without complications) only when documentation doesn't support a more specific option: with complications (K51.91).
Use an additional code to identify any associated fistulas, if applicable: anal fistula (K60.3-), anorectal fistula (K60.5-) and rectal fistula (K60.4-). Use an additional code to identify manifestations, such as: pyoderma gangrenosum (L88).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
More specific ulcerative chronic colitis codes (official index)
- with
- complication K51.919 — Ulcerative colitis, unspecified with unspecified complications
- abscess K51.914 — Ulcerative colitis, unspecified with abscess
- fistula K51.913 — Ulcerative colitis, unspecified with fistula
- obstruction K51.912 — Ulcerative colitis, unspecified with intestinal obstruction
- rectal bleeding K51.911 — Ulcerative colitis, unspecified with rectal bleeding
- specified complication NEC K51.918 — Ulcerative colitis, unspecified with other complication
- enterocolitis
- ileocolitis
- mucosal proctocolitis
- proctitis
- pseudopolyposis
- psychogenic F54 — Psychological and behavioral factors associated with disorders or diseases classified elsewhere
- rectosigmoiditis
- specified type NEC K51.80 — Other ulcerative colitis without complications
- with
- complication K51.819 — Other ulcerative colitis with unspecified complications
- abscess K51.814 — Other ulcerative colitis with abscess
- fistula K51.813 — Other ulcerative colitis with fistula
- obstruction K51.812 — Other ulcerative colitis with intestinal obstruction
- rectal bleeding K51.811 — Other ulcerative colitis with rectal bleeding
- specified complication NEC K51.818 — Other ulcerative colitis with other complication
Common questions about ulcerative chronic colitis ICD-10 codes
What is the ICD-10 code for ulcerative chronic colitis?
- K51.90 — Ulcerative colitis, unspecified, without complications. More specific codes apply when the documentation supports them: K51.919, K51.914, K51.913, K51.912 and others below.
What is the ICD-10 code for psychogenic ulcerative chronic colitis?
- F54 — Psychological and behavioral factors associated with disorders or diseases classified elsewhere.
Is K51.90 billable?
- Yes. K51.90 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can K51.90 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict K51.90 as a principal diagnosis.
Is K51.90 a CC or MCC?
- K51.90 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.