ICD-10-CM 2027 diagnosis code
K52.831Collagenous colitis
K52.831 is a valid, billable ICD-10-CM code for collagenous colitis. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Code last changed in FY2017 (effective October 1, 2016). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About K52.831
K52.831 is the ICD-10-CM diagnosis code for Collagenous colitis. It belongs to category K52 (other and unspecified noninfective gastroenteritis and colitis), block K50-K52 (noninfective enteritis and colitis) and chapter 11 (diseases of the digestive system). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within K52.83 (microscopic colitis), K52.831 is specifically for Collagenous colitis. Related codes cover lymphocytic colitis (K52.832), other microscopic colitis (K52.838) and unspecified (K52.839).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 391 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders with MCC, relative weight 1.2392) and DRG 392 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders without MCC, relative weight 0.7645), in MDC 06 (Diseases and Disorders of the Digestive System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It was added in FY2017, effective October 1, 2016.
Before ICD-10, this condition was coded in ICD-9-CM as 558.9 (other and unspecified noninfectious gastroenteritis and colitis).
Notes that apply from higher levels
Instructions written at a parent level also apply to K52.831.
Broader instructions also apply from K50-K52 Noninfective enteritis and colitis and Chapter 11: Diseases of the digestive system.
Alphabetic index entries
1 entriesTerms in the official ICD-10-CM index that lead to K52.831.
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 06 · Diseases and Disorders of the Digestive System
ICD-9-CM equivalent
Converter →- 558.9Other and unspecified noninfectious gastroenteritis and colitisapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2017 (effective 10/1/2016): Added
- No changes since FY2017.
Common questions about K52.831
Is K52.831 billable?
- Yes. K52.831 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can K52.831 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict K52.831 as a principal diagnosis.
Is K52.831 a CC or MCC?
- No. K52.831 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does K52.831 group to?
- K52.831 is used in the MS-DRG v44.0 logic for MS-DRG 391 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders with MCC) and MS-DRG 392 (Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for K52.831?
- The CMS General Equivalence Mappings map K52.831 to ICD-9-CM 558.9.