2026 ICD-10-CM Diagnosis Code K52.838Other microscopic colitis

ICD-10-CM Codes›K00–K95›K50-K52›K52

ICD-10-CM K52.838
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K52.838 is a billable ICD-10-CM diagnosis code for other microscopic 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

ICD-10-CM Code
K52.838
Billable Status
Yes — Valid for Submission
Code Describes
Other microscopic colitis
Short Description
Other microscopic colitis
Same as the full description in the CMS dataset.
Parent Code
K52.83
Microscopic colitis

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK50-K52Noninfective enteritis and colitis
CategoryK52Other and unspecified noninfective gastroenteritis and colitis
This CodeK52.838Other microscopic colitis

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Colitis(acute) (catarrhal) (chronic) (noninfective) (hemorrhagic)
      • microscopic
        • specified NEC

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR DIG022
Noninfectious gastroenteritis
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Microscopic Colitis

    inflammation of the colon that is only apparent by microscopic examination.

Convert K52.838 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
558.9 Noninf gastroenterit NEC
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement K52.838 replaces the following previously assigned code(s):

  • K52.89 - Other specified noninfective gastroenteritis and colitis
FY 2018AddedAdded to the ICD-10-CM code setEffective October 1, 2017.
FY 2019–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About K52.838Overview

Is K52.838 (Microscopic colitis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other microscopic colitis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does K52.838 group to?

When other microscopic 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 K52.838?

Under the General Equivalence Mappings, other microscopic colitis converts to ICD-9-CM 558.9 (noninf gastroenterit NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.