Vascular disorders of the gastrointestinal tract

A wide range of vascular disorders and vasculitides may affect the gastrointestinal tract. Most are quite uncommon, but presentations are often dramatic with intestinal bleeding or gangrene. Intestinal ischaemia is most commonly due to atherosclerosis or thrombosis causing arterial or venous mesenteric vascular occlusion. There are four primary syndromes. (1) Ischaemic colitis—presents with abdominal pain, nausea, vomiting, and tenderness followed by passage of loose bloody stool. Supportive management is usually sufficient, but a key challenge is early identification of patients with severe injury who are likely to progress to transmural ulceration and perforation. (2) Acute mesenteric ischaemia—typically presents with sudden abdominal pain, initially without localizing signs such that diagnosis is often delayed. Priorities of management are resuscitation, exclusion of other causes of apparent abdominal catastrophe, and prompt laparotomy to resect ischaemic bowel. (3) Chronic mesenteric ischaemia—most often caused by atherosclerotic disease and presents with severe and poorly localized cramping abdominal pain after eating. Diagnosis requires evidence of vascular occlusion on imaging, and revascularization is the definitive management strategy. (4) Mesenteric venous thrombosis—diagnosis is most commonly via cross-sectional imaging. The mainstay of treatment is supportive, as well as anticoagulation and a search for predisposing factors. Vasculitides affecting the intestine may be primary or secondary. Abdominal symptoms rarely dominate the clinical picture. Vascular lesions of the gastrointestinal tract may present with acute haemorrhage, chronic iron deficiency anaemia, or obstruction. Lesions include angiodysplasias, telangiectasias, haemangiomas, Dieulafoy lesions, and gastric antral vascular ectasia. These lesions may occur in isolation or as part of a syndrome (e.g. hereditary haemorrhagic telangiectasia).