2026 ICD-10-CM Diagnosis Code K52.3Indeterminate colitis
ICD-10-CM Codes›K00–K95›K50-K52›K52
- Billable — Valid for Submission
- Not Chronic
K52.3 is a billable ICD-10-CM diagnosis code for indeterminate colitis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 391 through 392. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Noninfectious gastroenteritis.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Indeterminate colitis
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Colonic inflammatory bowel disease unclassified (IBDU)
Type 1 Excludes
- unspecified colitis K52.9
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Colitis (acute) (catarrhal) (chronic) (noninfective) (hemorrhagic) See Also: Enteritis; K52.9
indeterminate, so stated K52.3
Disease, diseased See Also: Syndrome;
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Convert K52.3 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code History & ChangesHistory
Replacement K52.3 replaces the following previously assigned code(s):
- K52.9 - Noninfective gastroenteritis and colitis, unspecified
Questions About K52.3Overview
What is the ICD-10 code for indeterminate colitis?
The ICD-10-CM code for indeterminate colitis is K52.3 (sometimes written as K523). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is K52.3 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report indeterminate colitis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does K52.3 group to?
When indeterminate colitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 391, 392, with relative weights from 0.7796 to 1.2683 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of K52.3?
Under the General Equivalence Mappings, indeterminate colitis converts to ICD-9-CM 558.9 (noninf gastroenterit NEC). The mapping is approximate, so confirm the match fits the documentation.
