ICD-10-CM 2027
ICD-10 code for Ileitis
From the official ICD-10-CM alphabetic index entry “Ileitis (chronic) (noninfectious)”. Page updated September 29, 2026.
About coding Ileitis
The ICD-10-CM code for Ileitis is K52.9 (Noninfective gastroenteritis and colitis, unspecified). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on K52.9.
Within K52, choose K52.9 (Noninfective gastroenteritis and colitis, unspecified) only when documentation doesn't support a more specific option: gastroenteritis and colitis due to radiation (K52.0), toxic gastroenteritis and colitis (K52.1), allergic and dietetic gastroenteritis and colitis (K52.2), indeterminate colitis (K52.3) and other specified noninfective gastroenteritis and colitis (K52.8).
Don't report K52.9 together with the conditions in its Excludes1 note: diarrhea NOS (R19.7), functional diarrhea (K59.1), infectious gastroenteritis and colitis NOS (A09), neonatal diarrhea (noninfective) (P78.3) and 1 more.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
More specific Ileitis codes (official index)
- backwash
- infectious A09 — Infectious gastroenteritis and colitis, unspecified
- regional (ulcerative)
- segmental
- terminal (ulcerative)
Don't confuse with (Excludes1 for K52.9)
Common questions about Ileitis ICD-10 codes
What is the ICD-10 code for Ileitis?
- K52.9 — Noninfective gastroenteritis and colitis, unspecified. More specific codes apply when the documentation supports them: A09.
What is the ICD-10 code for infectious ileitis?
- A09 — Infectious gastroenteritis and colitis, unspecified.
Is K52.9 billable?
- Yes. K52.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can K52.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict K52.9 as a principal diagnosis.
Is K52.9 a CC or MCC?
- No. K52.9 is neither a CC nor an MCC under MS-DRG v44.0.