Localized primary AL-type amyloidosis of the jejunum diagnosed by double-balloon enteroscopy.

A 56−year−old man presented with a 5− month history of upper abdominal pain and vomiting. Physical examination re− vealed a distended abdomen and high− pitched bowel sounds. Laboratory data were within reference ranges. He under− went abdominal ultrasound and comput− ed tomography, both of which showed significantly thickened jejunal loops. Eso− phagogastroduodenoscopy and ileocolo− noscopy were unremarkable and tissue specimens from the stomach, duodenum, rectum, colon, and ileum showed no ab− normalities on histological examination.