Less frequent causes of upper gastrointestinal bleeding.

Although they account for a minority of episodes of upper gastrointestinal bleeding, the awareness of less frequent causes of upper gastrointestinal bleeding can be crucial to the endoscopist in the evaluation of the patient with bleeding. This review discusses the Dieulafoy lesion, hemobilia, gastric antral vascular ectasia, Mallory-Weiss tear, and gastroduodenal arteriovenous malformation.