2026 ICD-10-CM Diagnosis Code K31.A29Gastric intestinal metaplasia with dysplasia, unspecified

ICD-10-CM Codes›K00–K95›K20-K31›K31

ICD-10-CM K31.A29
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K31.A29 is a billable ICD-10-CM diagnosis code for gastric intestinal metaplasia with dysplasia, unspecified. 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. Coders also document this condition as gastric dysplasia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified disorders of stomach and duodenum.

Code Identity

ICD-10-CM Code
K31.A29
Billable Status
Yes — Valid for Submission
Code Describes
Gastric intestinal metaplasia with dysplasia, unspecified
Short Description
Gastric intestinal metaplasia with dysplasia, unspecified
Same as the full description in the CMS dataset.
Parent Code
K31.A2
Gastric intestinal metaplasia with dysplasia

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK20-K31Diseases of esophagus, stomach and duodenum
CategoryK31Other diseases of stomach and duodenum
This CodeK31.A29Gastric intestinal metaplasia with dysplasia, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Gastric dysplasia
  • Gastric intestinal metaplasia
  • Intestinal metaplasia with dysplasia of gastric mucosa

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.

    • Metaplasia
      • gastric intestinal
        • with dysplasia

Clinical ClassificationClinical

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

CCSR DIG008
Other specified and unspecified disorders of stomach and duodenum
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Gastric Dysplasia

    a morphologic finding indicating the presence of dysplastic changes within the gastric mucosal epithelial cells.

  • Indefinite for Gastric Dysplasia|Indefinite for Gastric Intraepithelial Neoplasia

    a term used to describe an ambiguous morphologic pattern in the gastric mucosa, when there is doubt whether the findings represent a non-neoplastic or neoplastic pathologic process.

  • Negative for Gastric Dysplasia|Negative for Gastric Intraepithelial Neoplasia

    a morphologic finding indicating the absence of dysplastic changes in the gastric mucosal epithelium. it includes non-neoplastic inflammatory, reactive, or metaplastic pathologic processes.

  • Gastric Intestinal Metaplasia

    a morphologic finding indicating the replacement of part of the gastric mucosal epithelium with intestinal-type epithelium. using immunohistochemical staining, gastric intestinal metaplasia is classified as complete or incomplete. complete intestinal metaplasia is defined by the decreased expression of gastric mucins and expression of the intestinal mucin muc2. incomplete intestinal metaplasia is defined by the co-expression of both gastric mucins and muc2.

  • Intestinal Metaplasia of Gastric Mucosa|Gastric Intestinal Metaplasia

    a morphologic finding indicating the replacement of part of the gastric mucosal epithelium with intestinal-type epithelium. using immunohistochemical staining, gastric intestinal metaplasia is classified as complete or incomplete. complete intestinal metaplasia is defined by the decreased expression of gastric mucins and expression of the intestinal mucin muc2. incomplete intestinal metaplasia is defined by the co-expression of both gastric mucins and muc2.

Code History & ChangesHistory

Replacement K31.A29 replaces the following previously assigned code(s):

  • K31.89 - Other diseases of stomach and duodenum
FY 2022AddedAdded to the ICD-10-CM code setEffective October 1, 2021.
FY 2023–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About K31.A29Overview

Is K31.A29 (Gastric intestinal metaplasia with dysplasia) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report gastric intestinal metaplasia with dysplasia, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does K31.A29 group to?

When gastric intestinal metaplasia with dysplasia, unspecified 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.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.