Mesenteric vein thrombosis. Four cases and review of the literature.

Mesenteric vein thrombosis, an uncommon but important clinical entity, can cause ischemia or infarction of the small intestine. Mesenteric vein thrombosis was first described nearly a century ago, but diagnosis remains difficult because it can affect young individuals without any known predisposing disorder and because patients often present with nonspecific abdominal symptoms. We report 4 cases of small intestinal ischemia secondary to superior mesenteric vein thrombosis. Three were due to hypercoagulable states (protein-S deficiency, factor-VII abnormalities) and one was idiopathic. In recent years, the development of modern imaging techniques (particularly ultrasonography, duplex scanning, and computed tomography) have enabled early recognition of this disease. Anticoagulation is therapeutic acutely unless there are signs of peritonitis which necessitate surgical resection of the infarcted bowel.