Small bowel stricture as a late sequela of superior mesenteric vein thrombosis

The increasing frequency of use of CT in patients with acute abdomen is likely to improve the diagnosis of rarely occurring conditions/causes such as superior mesenteric vein thrombosis (MVT). Despite its severe consequences, MVT often presents with nonspecific clinical features.

AD, a 64-year-old man was an emergency admission with vague abdominal discomfort of two weeks duration, acute upper abdominal pain, loose stools, fresh rectal bleeding and vomiting. A contrast enhanced abdominal CT showed thrombosis of the proximal portal vein and the entire length of the superior mesenteric vein (SMV) with small bowel ischaemia extending from the terminal ileum to the mid jejunal loops. Tests for paroxysmal nocturnal haemoglobinuria and Janus kinase 2 mutation yielded negative results. AD was readmitted seven months later with small bowel obstruction requiring segmental small bowel resection with end-to-end anastomosis. Abdominal CT had shown complete resolution of MVT but a small bowel stricture.

Thrombosis limited to mesenteric veins results in earlier and more frequent development of infarction compared to portal combined with mesenteric venous thrombosis. Most patients may be successfully treated with anti-coagulation therapy alone. However, surgery may be required to deal with intestinal infarction or late sequela of MVT.

This case demonstrates that MVT can be reversed by effective anticoagulation. However, the price paid for a mild to moderate effect on the bowel may be significant stricture later on. Patients escaping early bowel resection due to massive MVT leading to bowel infarction may still require resection later due to stricture.