Natural history of gastritis and its relationship to peptic ulcer disease.

Chronic gastritis is a common inflammatory disease. In a number of patients, the inflamed gastric mucosa shows a gradual tendency to become atrophic (atrophic gastritis). Gastritis tends to be lifelong, and spontaneous healing is rare. With very few exceptions (e.g. in patients with autoimmune chronic corpus gastritis), gastritis is associated with the presence of the bacterium Helicobacter pylori. Inflammation and atrophy of the gastric mucosa result in impairment of gastric secretory functions (e.g. secretion of gastric acid, pepsin and gastrin). Such impairment is dependent on the topographic type of gastritis; i.e. whether the inflammation and atrophy occur in the antrum (chronic antral gastritis), corpus (chronic corpus gastritis) or in both the antrum and corpus simultaneously (chronic pangastritis). Gastritis of different topographic types associates with different gastric diseases. In patients with H. pylori-related antral or pangastritis, peptic ulcer disease, and in particular duodenal ulcer, is common (with an incidence exceeding 20% after 10 years' follow-up), as compared with peptic ulcer disease, which is very rare in patients with a normal stomach. Gastric ulcer may sometimes occur in patients with a rather atrophic stomach, but both gastric and duodenal ulcers are extremely rare in patients in whom the gastritis accompanies severe atrophic changes in the corpus mucosa. Routine biopsies from the antrum and corpus, and interpretation of the results in the light of the data on gastritis and its atrophic sequelae, allow the gastroenterologist to predict the risk and likelihood of peptic ulcer disease in patients with gastritis.