Chronic gastrointestinal bleeding of unknown cause.
D000368:Aged; D001165:Arteriovenous Malformations / Q000150:complications*; D002432:Cecum / Q000002:abnormalities / Q000098:blood supply*; D002908:Chronic Disease; D006471:Gastrointestinal Hemorrhage / Q000209:etiology*; D006801:Humans; D008297:Male; D012007:Rectum