ICD-10 Code K55.039 – Acute (reversible) ischemia of large intestine, extent unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K55.039 – Acute (reversible) ischemia of large intestine, extent unspecified
What it is
K55.039 identifies a sudden, potentially reversible reduction in blood flow to the large intestine when the affected extent is not specified in the record. Use it for ischemic injury of the colon without documentation of infarction.
Clinical signs
Common findings include abdominal pain, cramping, and bloody or maroon stools. Clinical features vary; refer to documentation for imaging, endoscopic, or surgical evidence supporting large-intestine ischemia.
When to use this code
Use this code when the provider documents acute or reversible ischemia of the colon and does not specify the extent of involvement. It is appropriate when the record supports ischemia but not gangrene or infarction. If the note only says “ischemic colitis,” check documentation for the exact diagnosis.
Do not use for
Do not use K55.039 for chronic mesenteric ischemia, intestinal infarction, or gangrene. If the provider documents a different bowel segment or a more specific ischemic condition, code that instead.
Coding tip
Query for the affected extent and whether infarction is present before assigning K55.039.