Ischemic colitis

Abstract

The large bowel accounts for roughly half of all episodes of gastrointestinal ischemia. The extent of damage to the colon will depend on the duration and cause of ischemic injury, the involved blood vessel type and its localization, as well as the possibility of collateral vascular supply. Three major manifestations of ischemic injury to the colon can be distinguished: massive bowel infarction (gangrenous colitis), hemorrhagic enterocolitis, and ischemic colitis (non-gangrenous colitis). Ischemic colitis, usually due to subacute colonic ischemia, is the most common form. The disease can be reversible or irreversible. It affects mainly elderly, but younger patients can also show features of ischemic colitis in particular situations. It occurs on the mucosal side (ulcero-inflammatory pattern) or transmural (cobble-stoning and strictures). Histology shows a characteristic picture with variable cell necrosis, minimal inflammation, and hyalinization of the lamina propria.