Ralph T, a 45-year-old store manager. He has a burning feeling in his stomach. The pain is absent when he awakens, appears in midmorning, and is relieved by food but recurs two to three hours after a meal. The pain often awakens him at 1 or 2 A.M. The doctor orders a blood test. Then the doctor orders a procedure where they put a tube down his mouth. He also has to drink some bad tasting, chalky liquid and get an X-ray of his stomach. What does he have He complains of pain in the epigastric region. An endoscopic examination and x-ray studies with barium showed normal stomach function. Gastric analysis demonstrated that the gastric juice pH fell to 1.9 with pentagastrin stimulation (6 ug/kg s.c.). Fasting serum gastrin levels were normal. A blood test was performed and was found positive for a bacterial antigen