Irritation and inflammation of the esophagus is known as esophagitis. Esophagus is the tube that carries food from back of the mouth to the stomach. There are two forms of esophagitis; primary and reflux. Primary esophagitis is caused by a physical irritant and is characterized by spasm and obstruction, with pain on swallowing or palpation, profuse salivation, regurgitation of slimy, blood-stained saliva and feed, and possible stricture formation.
Reflux esophagitis in dogs is an inflammation of the esophagus, but it is caused by the backward flow of gastric or intestinal fluid. This liquid will start to irritate the esophagus, and thus causes both inflammation and ulceration. This form can also be caused by frequent vomiting, cancer, or a hernia, but they are not the most common cause.
Young dogs with congenital esophagus abnormalities are at an increased risk of esophagitis while older dogs that are being treated with anesthesia for surgery or other reason, may develop this condition. Complications include esophageal stricture, megaesophagus, esophageal perforation and esophageal fistula formation but aspiration pneumonia is the most important complication of esophagitis and it is caused by food or liquid particles entering the lungs.
Common symptoms associated with esophagitis include regurgitation, increased swallowing motions, pain and difficulty while swallowing, excessive salivation, inability to ingest food, reluctance to move or to lie down, poor appetite, weight loss, coughing and fever. Additionally, the dog may extends its head and neck during swallowing and exhibit pain when touched on its neck or esophagus.