superior mesenteric vein thrombosis

Thrombosis often occurs secondary to: 1. Portal vein congestion and blood stasis caused by cirrhosis or extrahepatic compression. 2. Intra-abdominal purulent infections, such as gangrenous appendicitis, ulcerative colitis, strangulated hernia, etc. 3. Certain blood abnormalities, such as polycythemia vera or hypercoagulable states caused by oral contraceptives. 4. Injury caused by trauma or surgery, such as mesenteric hematoma, splenectomy, right hemicolectomy, etc. Approximately one-quarter of patients have no obvious predisposing cause, termed primary mesenteric venous thrombosis.