Antithrombin III deficiency appearing as mesenteric vein thrombosis.

Mesenteric vein thrombosis is a relatively uncommon but devastating problem. Absence of any of the generally accepted etiologic factors of mesenteric vein thrombosis has lead to the diagnosis of "primary" mesenteric vein thrombosis in 25-55% of all cases. In this report we identify a young man with antithrombin III deficiency presenting as "primary" mesenteric vein thrombosis with massive bowel infarction. It again raises the possibility that other cases of "primary" mesenteric vein thrombosis may have been associated with this coagulopathy. Factors influencing antithrombin III levels are discussed in relation to diagnosis of the familial deficiency state in a patient with mesenteric vein thrombosis. The association of intra-abdominal venous occlusion and antithrombin III deficiency is emphasized.