gastric mucosal atrophy
Monday 7 March 2005
Atrophy of the stomach affects primarily the glands, which become sparse and small. In atrophy of the gastric corpus and fundus, parietal and chief cells disappear from the oxyntic glands, and the residual glands may undergo pseudopyloric metaplasia.
Mucosal atrophy can be noted grossly, especially in advanced, diffuse atrophy of oxyntic mucosa in the fundus and corpus where rugae disappear and underlying blood vessels become visible.
On the other hand, mucosal thinning is often grossly inapparent in the antrum, probably because its overall thickness is preserved by accompanying inflammation, intestinal metaplasia, or foveolar hyperplasia.
Atrophy is often associated with intestinal metaplasia, but these two features may occur independently of each other.
In pernicious anemia (corpus-predominant atrophic gastritis), there may be little or no intestinal metaplasia in large areas of the atrophic stomach; in contrast, scattered goblet cells may be found in the surface and foveolar epithelium of many nonatrophic H. pylori-infected stomachs.
When metaplastic epithelium replaces the specialized epithelium of the mucous glands in the antrum or oxyntic glands in the corpus, however, there is actual loss of functional glandular tissue, and therefore true atrophy. In such an instance, atrophy and intestinal metaplasia coincide.
A distinctive form of gastric atrophy occurs in patients who undergo subtotal gastrectomy (antrectomy). Since there is reduced gastrin stimulation, parietal cells diminish in number in the residual stomach and the oxyntic mucosa becomes thinned.
multifocal atrophic gastritis