A veterinarian checks a cat's vitals.

Megaesophagus in Dogs and Cats

Overview of Megaesophagus

Megaesophagus is a condition where there is decreased or absent motility (movement, muscular contractions) of the esophagus. The esophagus is the tube that carries food and water from the throat to the dog’s stomach. With megaesophagus, passing food all the way to the stomach becomes difficult, and the food may be regurgitated back up into the throat or aspirated into the lungs causing aspiration pneumonia. This reduced motility usually results in dilation of the esophagus. This is commonly due to an underlying abnormality of the nervous system.

Megaesophagus can be acquired or congenital.

Affected animals may have difficulty maintaining adequate nutrition, due to their inability to move food into the gastrointestinal tract. They may also develop pneumonia secondary to regurgitation and aspiration of foodstuffs into the lungs.

Megaesophagus is seen in both dogs and cats, however, it is much more common in dogs. Any breed can be affected. It may be hereditary in the Wire Hair Fox Terrier, Jack Russell Terrier, Springer Spaniel, Smooth Fox Terrier, Samoyed, and Miniature Schnauzer. Other breeds affected include the German Shepherd, Newfoundland, Great Dane, Irish Setter, Chinese Shar-Pei, Pug, Labrador Retriever, Dachshund, and Greyhound. Siamese cats have an increased incidence. Both sexes can be affected with a slight increased incidence in young female dogs.

Common Symptoms

Diagnosis of Megaesophagus

A thorough description of the clinical signs is very important and can often be the key to the diagnosis. A complete history is especially important in these cases, as regurgitation, the most common clinical sign seen with megaesophagus is often referred to as vomiting by the pet owner. It is most important that your veterinarian understands exactly what signs your pet is exhibiting at home.

A complete diagnostic evaluation is necessary to exclude other disease processes that may cause similar symptoms, make a definitive diagnosis of megaesophagus, develop the optimal treatment plan, and understand the prognosis.

Tests may include:

Your veterinarian may recommend additional tests to exclude or diagnose other conditions, such as the following:

A Closer Look at Megaesophagus

Because of an animal’s history, physical examination findings and overall presentation are variable, and there are other illnesses that must be ruled out when establishing a definitive diagnosis. It is important to note that regurgitation, which is the effortless evacuation of fluid, mucus, and undigested food from the esophagus, is the most common clinical sign associated with megaesophagus. Regurgitation must be differentiated from vomiting, which is the forceful evacuation of digested food from the stomach.

The following are often associated with regurgitation:

Megaesophagus may occur as a component of several systemic diseases, such as:

Treatment for Megaesophagus

The primary goals in treating megaesophagus are identification and treatment of the underlying cause, limiting the frequency of regurgitation, preventing over-distention of the esophagus, providing adequate nutrition, feeding in an upright position, and treating complications such as aspiration, pneumonia, and esophagitis. In cases where a primary cause can be identified and treated, esophageal motility may improve with time. Treatment is symptomatic in animals in which an underlying cause cannot be identified.

Following appropriate feeding recommendations is of paramount importance, and, although there is no single way that all animals should be fed, several general principles apply:

Other treatment options for megaesophagus include:

Animals with severe aspiration pneumonia require special attention and aggressive therapy.

Home Care and Prevention of Megaesophagus

Optimal treatment for your pet requires a combination of home and professional veterinary care. There is no single therapy that is recommended for all animals with megaesophagus. Each case is unique, and specific recommendations are tailored for each patient.

Most causes of megaesophagus cannot be prevented. However, megaesophagus associated with ingestion of certain types of foreign bodies or toxins may be prevented by closely monitoring your dog’s environment.

Prognosis for Megaesophagus

Prognosis is often poor for dogs with megaesophagus. Diagnosis and treatment of any underlying condition is important to optimize prognosis. It is estimated that 20 to 50% of cases recover and approximately 50% of cases respond to therapy. Progressive emaciation and aspiration pneumonia are the two most common causes of death and generally lead to euthanasia after diagnosis. Excellent veterinary care and client dedication are critical.