2026 ICD-10-CM Diagnosis Code K55.029Acute infarction of small intestine, extent unspecified

ICD-10-CM Codes›K00–K95›K55-K64›K55

ICD-10-CM K55.029
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K55.029 is a billable ICD-10-CM diagnosis code for acute infarction of small intestine, extent unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 393 through 395. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified gastrointestinal disorders and Peripheral and visceral vascular disease.

Code Identity

ICD-10-CM Code
K55.029
Billable Status
Yes — Valid for Submission
Code Describes
Acute infarction of small intestine, extent unspecified
Short Description
Acute infarction of small intestine, extent unspecified
Same as the full description in the CMS dataset.
Parent Code
K55.02
Acute infarction of small intestine

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK55-K64Other diseases of intestines
CategoryK55Vascular disorders of intestine
This CodeK55.029Acute infarction of small intestine, extent unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute bowel infarction
  • Acute GIT vascular insufficiency
  • Acute infarction of small intestine
  • Acute vascular insufficiency of intestine
  • Anastomotic necrosis of small intestine
  • Duodenal anastomotic necrosis
  • Gangrene of mesentery of ileum
  • Gangrene of mesentery of jejunum
  • Gangrene of mesentery of small intestine
  • Gangrene of terminal ileum
  • Gastrointestinal anastomotic necrosis
  • Ileal gangrene
  • Infarction of small intestine
  • Infarction of small intestine due to mesenteric vein thrombosis
  • Jejunal gangrene
  • Mesenteric gangrene
  • Necrotic enteritis of intestine
  • Small intestinal gangrene
  • Thrombotic infarction

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.

    • Infarct, infarction
      • intestine (acute) (agnogenic) (embolic) (hemorrhagic) (nonocclusive) (nonthrombotic) (occlusive) (thrombotic) (with gangrene)
        • small

Clinical ClassificationClinical

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

CCSR DIG025
Other specified and unspecified gastrointestinal disorders
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR CIR026
Peripheral and visceral vascular disease
Default principal diagnosis: inpatient No · outpatient No

Convert K55.029 to ICD-9-CMHistory

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

ICD-9-CM
557.0 Ac vasc insuff intestine
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement K55.029 replaces the following previously assigned code(s):

  • K55.0 - Acute vascular disorders of intestine
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 K55.029Overview

Is K55.029 (Acute infarction of small intestine) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute infarction of small intestine, extent unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does K55.029 group to?

When acute infarction of small intestine, extent unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 393, 394, 395, with relative weights from 0.6490 to 1.5993 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of K55.029?

Under the General Equivalence Mappings, acute infarction of small intestine, extent unspecified converts to ICD-9-CM 557.0 (ac vasc insuff intestine). The mapping is approximate, so confirm the match fits the documentation.

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.