Structural and ultrastructural alterations, exfoliative cytology and enzyme cytochemistry and histochemistry, proliferation kinetics, immunological derangements and other causes, and clinical associations and sequallae.

Our main purpose in this review article is to present some of the vast amount of information on the subject of atrophic gastritis available at the present time. Various areas of research pertaining to this entity, including that from the author's laboratory, are reviewed in this article, encompassing histological and ultrastructural abnormalities, enzyme histochemistry, and exfoliative cytology and cytochemistry of chronic gastritis, with emphasis on the diagnostic significance of these laboratory methods. The altered cell proliferation kinetics in atrophic gastric lesions is also discussed, as well as its significance in the proliferation and reduction of glandular cells of the gastric mucosa. Furthermore, some of the more recent evidence of immunological mechanisms and other causes of chronic gastritis, such as chronic alcoholism and bile reflux, is reviewed, as well as the effects of partial gastrectomy on the gastric mucosa. The important associations and sequellae of atrophic gastritis, such as gastric ulcer, gastric polyps, and gastric cancer, are discussed in detail.