Inflammation of the lining of the STOMACH. This may take an acute form when excess alcohol or other irritating substances have been ingested, resulting in vomiting. The common cause of chronic gastritis is infection with HELICOBACTER PYLORI. Or it may be the result of regular smoking and chronic alcoholism; or back-flow of BILE from the DUODENUM. Sufferers are at risk of gastric ulcers or carcinoma. Atrophic gastritis, when the mucosal lining of the stomach withers away, may follow chronic gastritis but sometimes occurs as an AUTOIMMUNE disorder.