Bronchoesophageal fistulas rarely occur in dogs and cats. They most commonly develop secondary to foreign body penetration of the esophagus. Fistulas may develop between the esophagus and any part of the respiratory tree. A congenital form has been described, and Cairn Terriers may be predisposed. The most common clinical sign is coughing after eating or drinking. Regurgitation may also occur, and anorexia, fever, and lethargy may be related to pneumonia.
Survey radiographs may reveal a radiopaque foreign body and pneumonia. Contrast esophagrams will show the communication between the esophagus and airways. Use of a small amount of barium is recommended—iodinated contrast agents are hyperosmolar and can cause pulmonary edema.
Surgical correction consisting of a lung lobectomy and repair of the defect in the esophagus is required. The prognosis after surgery is good.