Chronic gastritis observed from a standpoint of chronic organ inflammation

The muco-muscularis ratio (MMR) of the pyloric antrum was examined in "normal' stomachs and stomachs with chronic gastritis, small chronic gastric ulcers, and duodenal ulcers. The majority of normal stomachs revealed a figure of less than 1 (average 0.803). In chronic gastritis, the MMR was rather high (average 1.127). This fact indicated that the characteristic feature in this condition was atrophy of the muscularis externa rather than that of the mucous membrane. The MMR in stomachs with small chronic ulcers showed no significant difference compared with that of normal samples. Although there were greater fluctuations in MMR of stomachs in cases with duodenal ulcers, it was generally high (average 1.233). The age distribution in this group simulated that of the chronic gastritis group. Microscopical examination of the gastric mucosa of the pyloric antrum in chronic gastritis revealed physiological inflammatory changes appearing 20 years earlier than those of aging process. The pattern of microscopical findings in the stomach with small chronic ulcers was similar to that of normal stomach, and the formation of ulcer was interpreted to be a result of an episode occurring locally. In the stomach of cases with duodenal ulcers, other than the low incidence of intestinal metaplasia, the general findings were similar to those seen in chronic gastritis.