Intestinal (mesenteric) vasculopathy. II. Ischemic colitis and chronic mesenteric ischemia.

Ischemic colitis accounts for approximately half of all cases of mesenteric vasculopathy. The clinical presentation varies depending on underlying cause, extent of vascular obstruction, rapidity of ischemic insult, degree of collateral circulation, and presence of comorbidity. Ischemic colitis is usually diagnosed by colonoscopy. Only approximately 20% of patients require surgery because of signs or laboratory findings of peritonitis or because of clinical deterioration. Approximately 20% of patients develop chronic colitis from irreversible colonic ischemic injury, which manifests clinically as persistent diarrhea, rectal bleeding, or weight loss and endoscopically as a colonic stricture or mass. Chronic mesenteric ischemia is almost always caused by significant atherosclerotic stenosis involving at least two mesenteric arteries, usually the superior mesenteric artery and celiac axis. The classic symptomatic triad of postprandial pain, fear of eating, and involuntary weight loss occurs with advanced disease.