Chronic gastritis is a common and frequent disease with an incidence of about 50-80% and increases with age, with a large degree of histological variability and inconsistent severity of symptoms and endoscopic and pathological changes. Common etiologies: H. pylori infection, autoimmune mechanisms and genetic factors, duodenal fluid reflux and associated with irritating foods, alcohol abuse, and NASID drug use. Common classification: Based on endoscopic manifestations and pathological histological changes, most hospitals in China still clinically classify it as chronic superficial gastritis (non-atrophic gastritis) and chronic atrophic gastritis. How to prevent chronic gastritis? 1, keep a happy spirit: depression or excessive tension and fatigue, easily caused by the pyloric sphincter dysfunction, bile reflux and chronic gastritis. 2, quit smoking and avoid alcohol: the harmful ingredients in tobacco can cause an increase in gastric acid secretion, which has a harmful stimulating effect on the gastric mucosa, and excessive smoking can cause bile reflux. The actual fact is that you can get a lot more than just a few of these. You should quit smoking and avoid alcohol. 3, caution, avoid using drugs that damage the gastric mucosa: long-term abuse of such drugs can cause damage to the gastric mucosa, resulting in chronic gastritis and ulcers. 4, active treatment of oropharyngeal infections: Do not swallow sputum, nasal discharge and other bacterial secretions into the stomach, resulting in chronic gastritis. 5, pay attention to diet: too acidic, too spicy and other irritating food and cold indigestible food should be avoided as far as possible, chew slowly when eating, so that the food is fully mixed with saliva, which is conducive to digestion and reduce the stimulation of the stomach. Diet should be regular and nutritious, and eat more food containing vitamin A, B and C. Avoid taking strong tea, strong coffee and other stimulating drinks. What is the prognosis? The prognosis is generally good. The majority of cases are Hp-associated gastritis, and there is little spontaneous clearance of Hp; therefore, chronic gastritis can persist, but most are asymptomatic. A small proportion of chronic superficial gastritis may develop into chronic multifocal atrophic gastritis, which is often combined with intestinal hyperplasia and, in a few cases, heterogeneous hyperplasia. A very small number of moderate and severe atrophic gastritis can develop into gastric cancer over a long period of time. The relationship between chronic gastritis and hp infection About 15-20% of Hp-associated gastritis will develop into peptic ulcer. Those with predominant inflammation of the gastric sinus are prone to duodenal ulcer, while multifocal atrophic gastritis is prone to gastric ulcer and has an increased risk of developing gastric cancer. The risk of gastric cancer is increased in chronic gastritis with heterogeneous hyperplasia, and the cancer rates are 2.53% for mild heterogeneous hyperplasia, 4-8% for moderate, and 10-83% for severe. the risk of gastric cancer increases 6-fold in Hp-infected patients, and the risk of gastric cancer is 5.8-fold higher in those with severe atrophy of the gastric body mucosa than in those without or with mild atrophy. lymphoma of gastric mucosa-associated lymphoid tissue can also occur in Hp-associated gastritis. Treatment (a) Diet and removal of unfavorable factors Eat a light diet, avoid irritating foods, rough foods, overheated drinks, alcohol abuse, salty foods, etc. Identify and get rid of all the causes of chronic gastritis as much as possible, stop taking medication, alcohol and smoking, etc. （The fear of chronic gastritis is more inclined to the fear that gastritis will become cancerous. Some clinical observations have found that neuroendocrine dysfunction and imbalance in gastrointestinal hormone release play a role in the pathogenesis of chronic gastritis. The lifestyle of patients with autonomic dysfunction manifested by tension, anxiety, agitation, irritability, and sadness should be given adequate attention in the treatment. At present, only atrophic gastritis is related to gastric cancer, so patients should be given proper health education to maintain an optimistic attitude towards life and avoid aggravating their mental burden. （The main function of gastric mucosal protective drugs is to enhance the barrier function of gastric mucosa and strengthen the ability of gastric mucosa to resist damaging factors. For those who have acid reflux, heartburn, stomach pain and gastroscopy suggesting mucosal erosion and bleeding, mucosal protective agents can be given. (1) Aluminum thioglycollate (2) Bismuth (3) Teprenone (2) Gastric stimulants Gastric and intestinal stimulants can be given to those with fullness and belching. 3.Acid suppressing drugs The gastric acid can be high or low in patients with chronic gastritis. The application of acid suppressing drugs can improve the PH value in the stomach, reduce the damage of H+ to the gastric mucosa, i.e. the degree of H+ counter-dispersion, and create a strong local environment for the inflammation repair of the gastric mucosa. 4.Hp eradication therapy: Hp positive active gastritis, Hp should be eradicated. 5.Other treatments: (1) Age-related atrophy and intestinalization; nutritive drugs for gastric mucosa, such as: carotene, folic acid, zinc, VitE, etc. (2) for gastric mucosal intestinal and atypical hyperplasia, give vitamin C, E and folic acid, regular endoscopic follow-up, chronic atrophic gastritis with severe heterogeneous hyperplasia in the current mostly considered precancerous lesions, advocate that surgical treatment should be considered, feasible endoscopic ESD complete excision of the lesion, without surgery but can achieve a curative effect. (3) Treatment of autoimmune gastritis: no special, pernicious anemia can be injected VitB12. dilute hydrochloric acid, digestive enzymes can be given to patients with poor digestive function.