2026 ICD-10-CM Diagnosis Code K55.059Acute (reversible) ischemia of intestine, part and extent unspecified

ICD-10-CM Codes›K00–K95›K55-K64›K55

ICD-10-CM K55.059
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K55.059 is a billable ICD-10-CM diagnosis code for acute (reversible) ischemia of intestine, part and 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
K55.059
Billable Status
Yes — Valid for Submission
Code Describes
Acute (reversible) ischemia of intestine, part and extent unspecified
Short Description
Acute ischemia of intestine, part and extent unspecified
Parent Code
K55.05
Acute (reversible) ischemia of intestine, part unspecified

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK55-K64Other diseases of intestines
CategoryK55Vascular disorders of intestine
This CodeK55.059Acute (reversible) ischemia of intestine, part and extent unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute GIT vascular insufficiency
  • Acute intestinal ischemia due to obstruction of vasculature of intestine
  • Acute ischemic colitis
  • Acute ischemic enteritis
  • Acute ischemic enterocolitis
  • Acute mesenteric arterial occlusion
  • Acute vascular insufficiency of intestine
  • Embolic infarction
  • Embolic mesenteric infarction
  • Fulminant enterocolitis
  • Hemorrhagic enteropathy of terminal ileum
  • Ileal hemorrhage
  • Inferior mesenteric artery embolus
  • Inferior mesenteric vein thrombosis
  • Insufficiency of mesenteric artery
  • Ischemic colitis
  • Ischemic enteritis of intestine
  • Ischemic enterocolitis
  • Mesenteric embolus
  • Mesenteric infarction
  • Occlusion of superior mesenteric artery
  • Occlusive mesenteric ischemia
  • Peripheral arterial insufficiency
  • Superior mesenteric artery embolus
  • Superior mesenteric artery thrombosis
  • Superior mesenteric vein thrombosis
  • Thrombosis of mesenteric artery
  • Thrombosis of mesenteric vein

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.

    • Embolism(multiple) (paradoxical)
      • artery
        • mesenteric (with gangrene)
    • Embolism(multiple) (paradoxical)
      • mesenteric (artery) (vein) (with gangrene)
    • Enterocolitis
      • fulminant ischemic
    • Enterocolitis
      • hemorrhagic (acute)
    • Enteropathy
      • hemorrhagic, terminal
    • Insufficiency, insufficient
      • vascular
        • intestine
          • acute
    • Ischemia, ischemic
      • bowel (transient)
        • acute
    • Ischemia, ischemic
      • intestine (large) (small) (transient)
        • acute
    • Ischemia, ischemic
      • mesenteric, acute
    • Narrowing
      • mesenteric artery

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 K55.059 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 K55.059 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 K55.059Overview

Is K55.059 (Acute (reversible) ischemia of intestine, part unspecified) a billable code?

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

What MS-DRG does K55.059 group to?

When acute (reversible) ischemia of intestine, part and 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 K55.059?

Under the General Equivalence Mappings, acute (reversible) ischemia of intestine, part and 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.