Edema and congestion of the esophageal mucosa is caused by esophagitis. Esophagitis (esophagitis) is an inflammatory disease of the esophageal mucosa caused by edema and congestion of the mucosa due to abnormal stimulation of the superficial or deep tissues of the esophagus. Diagnosis: 1. The disease begins with loss of appetite, followed by difficulty in swallowing, salivation and vomiting, often with refusal to eat or food reflux soon after swallowing. Dogs with acute esophagitis make abnormal grunting sounds due to gastric reflux, and mucus filaments adhere to the corners of the mouth. The esophagus is stiff and swollen to palpation. 2. Barium esophagogram. The mucosal surface of the esophagus is not smooth and there are band-like shadows. 3, esophageal endoscopy can directly examine the inflammatory state of the esophageal mucosa. 4, esophagitis its symptoms are mainly painful swallowing, difficulty, heartburn and pain behind the sternum mostly, when esophagitis is serious can cause esophageal spasm and esophageal stricture. When inflammation of the lower esophagus leads to mucosal degeneration followed by the growth of gastric columnar epithelial cells, it is called Barlow’s esophagus, which is the precursor of esophageal cancer and must be followed for a long time. Generally, bleeding in esophagitis is mild, but it may cause blood spitting or asphaltic stools. Under normal circumstances, stomach acid does not reflux into the esophagus. There is a high-pressure area in the lower part of the esophagus that blocks the reflux of stomach acid into the esophagus, but if the cardia becomes loose for some reason, the pressure in the high-pressure area will drop or even disappear, and stomach acid and bile will reflux into the esophagus, stimulating the esophageal mucosa strongly and triggering esophagitis. After a meal lying down, eating too much, sweets or greasy food to eat too much can cause the stomach to reflux to the esophagus. When you feel “heartburn”, or “heartache”, or pain behind the sternum when drinking hot water or eating stimulating food, these are symptoms of esophagitis. The reason why you feel choking when swallowing food is due to esophageal edema, narrowing of the esophagus or spasmodic contraction of the esophageal wall due to inflammatory stimulation. Esophagitis should be treated promptly, otherwise it can worsen to the point of developing esophageal mucosal ulcers, and vomiting blood or blood in the stool.