Presentation of CaseA 21-year-old woman was admitted to the hospital because of abdominal pain and vomiting.She was well until seven years earlier, when she first experienced severe midepigastric pain that radiated to the back, accompanied by vomiting. During succeeding years she had repeated bouts of similar pain and vomiting and was admitted to a nearby hospital on 9 or 10 occasions. The attacks were accompanied by leukocytosis but never by documented elevation of bilirubin or amylase levels. Each episode resolved after three to six days on a clear-liquid diet and narcotics, and she felt well in the intervals. . . .