Serum gastrin in chronic gastritis.

Fasting gastrin levels in serum were measured in 49 patients with different types of chronic gastritis and in matched controls. In 15 patients with established pernicious anaemia the mean (+/- S.E. of mean) level of gastrin was greatly raised (699 +/- 99 pg/ml). In 17 patients with chronic atrophic gastritis, seropositive for parietal cell antibody but with adequate vitamin-B(12) absorption, the level was also raised (476 +/- 74 pg/ml). By contrast, in "simple" atrophic gastritis seronegative for parietal cell antibody the gastrin levels were significantly lower for both diffuse atrophic gastritis (129 +/- 31 pg/ml) and multifocal gastritis (14 +/- 4 pg/ml). These levels were similar to those in the controls (46 +/- 7 pg/ml).The mechanism of the raised gastrin levels remains uncertain, but neither achlorhydria nor in vivo action of the parietal cell antibody wholly accounted for the hypergastrinaemia.We conclude that hypergastrinaemia is characteristic of gastritis associated with autoimmune reactions to gastric antigens and pernicious anaemia and that a raised serum gastrin is a useful marker of the type of gastritis that tends to progress to the gastric lesion of pernicious anaemia. The findings suggest that this type of gastritis is an essentially different disease from "simple" atrophic gastritis, and the differences in gastrin levels may be due to sparing of the antral mucosa in the autoimmune type but not in "simple" gastritis.