ICD-10-CM 2027
ICD-10 code for gastric intestinal metaplasia
From the official ICD-10-CM alphabetic index entry “Metaplasia › gastric intestinal”. Page updated September 29, 2026.
About coding gastric intestinal metaplasia
The ICD-10-CM code for gastric intestinal metaplasia is K31.A0 (Gastric intestinal metaplasia, unspecified). The official index lists 10 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on K31.A0.
Within K31.A, choose K31.A0 (unspecified) only when documentation doesn't support a more specific option: without dysplasia (K31.A1) and with dysplasia (K31.A2).
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.
More specific gastric intestinal metaplasia codes (official index)
- with dysplasia K31.A29 — Gastric intestinal metaplasia with dysplasia, unspecified
- high grade K31.A22 — Gastric intestinal metaplasia with high grade dysplasia
- low grade K31.A21 — Gastric intestinal metaplasia with low grade dysplasia
- indefinite for dysplasia K31.A0 — Gastric intestinal metaplasia, unspecified
- without dysplasia K31.A19 — Gastric intestinal metaplasia without dysplasia, unspecified site
- involving
- antrum K31.A11 — Gastric intestinal metaplasia without dysplasia, involving the antrum
- body (corpus) K31.A12 — Gastric intestinal metaplasia without dysplasia, involving the body (corpus)
- cardia K31.A14 — Gastric intestinal metaplasia without dysplasia, involving the cardia
- fundus K31.A13 — Gastric intestinal metaplasia without dysplasia, involving the fundus
- multiple sites K31.A15 — Gastric intestinal metaplasia without dysplasia, involving multiple sites
Common questions about gastric intestinal metaplasia ICD-10 codes
What is the ICD-10 code for gastric intestinal metaplasia?
- K31.A0 — Gastric intestinal metaplasia, unspecified. More specific codes apply when the documentation supports them: K31.A29, K31.A22, K31.A21, K31.A0 and others below.
What is the ICD-10 code for indefinite for dysplasia gastric intestinal metaplasia?
- K31.A0 — Gastric intestinal metaplasia, unspecified.
Is K31.A0 billable?
- Yes. K31.A0 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can K31.A0 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict K31.A0 as a principal diagnosis.
Is K31.A0 a CC or MCC?
- No. K31.A0 is neither a CC nor an MCC under MS-DRG v44.0.