[Mesenteric venous thrombosis and antithrombin III deficiency: diagnosis before an acute digestive hemorrhage].

Mesenteric venous thromboses are often associated with antithrombin III deficiency. We can suspect this clinical diagnosis in patients with nonspecific abdominal pain syndrome and personal or familial history of mesenteric venous thrombosis. We report the case of a 63-old-male caucasian with antithrombin III deficiency and rectal bleeding who was diagnosed with mesenteric venous thrombosis at exploratory laparotomy. This case emphasizes the necessity of a careful history in all patients without an obvious diagnosis. In this way, we can invoke the diagnosis of mesenteric venous thrombosis quickly and begin the heparin therapy while waiting for the results of further confirmatory tests.