Types of chronic gastritis

Chronic gastritis develops in three patterns:

1. Antral, with high acid production and high risk of duodenal ulcer.
2. Pangastritis with multifocal mucosal atrophy, low acid secretion and higher risk of adenocarcinoma.
3. Autoimmune gastritis (less than 10% of chronic gastritis) - autoantibodies to parietal cells and H,K-ATPase --> gland destruction and mucosal atrophy --> loss of acid and intrinsic factor production --> pernicious anaemia (associated with Hashimoto thyroiditis, Addison disease, and other autoimmunes).