ICD-10 Code K55.03 – Acute (reversible) ischemia of large intestine (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K55.03 – Acute (reversible) ischemia of large intestine
What it is
K55.03 identifies acute, reversible reduced blood flow to the large intestine. It means the colon is temporarily underperfused, but the injury is not documented as irreversible bowel infarction.
Clinical signs
Typical findings include sudden abdominal pain, cramping, and possible bloody stool or diarrhea. Clinical features vary; refer to documentation for evidence of ischemia, reversibility, and the affected bowel segment.
When to use this code
Use K55.03 when the provider documents acute ischemia of the large intestine and indicates it is reversible or transient. Apply it when the record supports colon ischemia without gangrene, infarction, or chronic ischemic disease. If the note is unclear, check documentation.
Do not use for
Do not use this code for ischemia of the small intestine, chronic mesenteric ischemia, or bowel infarction. If the documentation instead describes necrosis or gangrene, select the more specific code.
Coding tip
Verify that the documentation says “large intestine” and “reversible” before assigning K55.03.