Acute Ischemic Colitis – Symptoms, Signs, Diagnosis, Treatment

Acute Ischemic Colitis

Acute ischemic colitis refers to an inflammation of the colon (a part of the large intestine) due to impairment of the blood flow to the colon. Sudden left side abdominal pain and blood in the bowel movement, appearing in a person after 50 years of age, are characteristic symptoms. The resulting injury of the colonic wall may be mild or severe ( requiring an urgent surgery).

A common term used for ischemic injury of small or large intestine or both is acute mesenteric ischemia (mesenteric arteries are those that supply the bowel).

Symptoms and Signs

Symptoms of acute intestinal ischemia appear suddenly (in minutes) and may include:

  • Lower or upper left side abdominal pain. Pain may be quite severe but abdominal wall, when checked by a doctor, typically is not tender (but becomes tender if the colon is
  • Bright red blood in the bowel movement or bloody mucus or bloody diarrhea

Causes of Acute Ischemic Colitis

Blood flow impairment causing acute ischemic colitis may result from:

  • Blood clot in one of the abdominal arteries or veins due to arterial or venous thrombosis (increased blood clotting)
  • Medications: non-steroid antinflammatory drugs (NSAIDs), estrogen replacement therapy, migraine medications, blood pressure pills, heart drug digoxin, pseudoephedrine, alosterone (Lotronex) used in IBS
  • Vasculitis (inflammation of arteries)
  • Abdominal surgery like surgery of aneurysm of abdominal aorta
  • Sudden fall in blood pressure due to heart attack, arrhythmia, shock
  • Abdominal trauma
  • Infection of the colon by E.coli, citomegalovirus, entameba etc (in severe food poisoning).
  • Colon cancer that obstructs the colon
  • Radiation injury
  • Pheocromocytoma (a rare tumor of adrenal gland that secretes adrenaline that causes constriction of abdominal blood vessels)
  • More causes of acute ischemic colitis


In acute left abdominal pain investigations in the following order are recommended:

  1. X-ray of abdomen without and with barium enema
  2. CT of abdomen

Angiography and MRI may be used to evaluate changes in the arteries.


The aim of the treatment of acute ischemic colitis is to re-establish normal blood supply to the colon as soon as possible. Intravenous infusion is given to maintain appropriate blood pressure. Surgery is often needed to make a bypass around the obstructed artery, or to remove permanently damaged parts of the colon (2).

Related articles:

Chronic Ischemic Colitis
Chronic Colitis
Blood in the Stool
Left Side Abdominal Pain


  1. Causes of acute ischemic colitis  (
  2. Surgical treatment of acute mesenteric ischemia  (
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