Retroperitoneal bleeding due to a ruptured aneurysm of the middle colic artery.

In a 51-year-old man the middle colic artery ruptured. The patient had abdominal pain for several days, and then suddenly, a considerable intraperitoneal bleeding occurred. The aneurysm was extirpated and in the postoperative angiogram, numerous aneurysms were detected in the colic artery. Splanchnic artery aneurysm mainly occurs in renal artery, splenic artery and hepatic artery, but rarely in the mesenteric artery. The pathogenesis of mesenteric artery aneurysms is usually mycotic false aneurysm from prior aortic endoarteritis. In the present case, the etiology of the aneurysm was not confirmed.