Autoimmune atrophic gastritis with hypergastrinemia.

Elevation in fasting serum gastrin levels was found in three patients being evaluated for persistent upper abdominal pain without radiographic evidence of peptic ulcer disease. Fiberoptic endoscopy of the upper gastrointestinal tract in each patient revealed characteristic changes of chronic atrophic gastritis. Gastric biopsies showed diffuse chronic inflammation in the lamina propria, a decrease in the number of parietal cells, and "intestinalization" of gastric mucosa. Total achlorhydria was demonstrated after a maximal histalog stimulus; however, serum levels of vitamin B12 and Schilling test values were normal in all three patients. Parietal cell antibodies were found in the serum in all patients in a dilution of 1:20 to 1:80. These cases represent autoimmune (type A) chronic atrophic gastritis and should be distinguished from chronic simple (type B) gastritis, in which serum gastrin levels are normal and no parietal cell antibodies are found in the serum. Patients with autoimmune gastritis should be observed at frequent intervals for the occurrence of pernicious anemia or gastric carcinoma.