Intraoperative endoscopic localization of jejunal angiodysplasia as a source of massive rectal bleeding.

Gastrointestinal bleeding from an unknown source presents a difficult diagnostic problem. Despite the number of diagnostic tests available, there are occasions when gastrointestinal bleeding requires operative intervention without preoperative localization of the bleeding site. This situation was encountered in the case described, in which a preoperative bleeding scan could only suggest that the small bowel in the left upper quadrant was the source of the bleeding. Intraoperative small-bowel endoscopy was important in confirming the diagnosis.