Megaesophagus in Dogs
The esophagus is the tube-shaped organ that carries swallowed food and water from the mouth down into the stomach. Megaesophagus (ME) is described as decreased movement and dilation or enlargement of the esophagus. The esophagus has muscles and nerves which normally help move the food and water to the stomach. When the esophagus dilates and doesn’t function normally, food can sit in the esophagus or be brought back up through the throat and out the mouth (regurgitation). Keep reading to learn how megaesophagus is diagnosed and treated in dogs.
Pets with megaesophagus are at increased risk for developing aspiration pneumonitis or a lung infection because they can accidentally inhale food and liquid that they regurgitate.
Megaesophagus occurs more often in dogs but can also occur in cats. Pets can be born with ME or it can happen later in life. Breeds at risk genetically include Wire-Haired Fox Terriers, Miniature Schnauzers, German Shepherds, Newfoundlands, Great Danes, Irish Setters, Shar-Peis, Pugs, Greyhounds, and the Siamese Cat.
Causes of Megaesophagus in Dogs
ME can be a primary disease or secondary to another disease such as Myasthenia Gravis. Myasthenia Gravis is the most common disorder causing ME.
The cause of primary ME is unknown (idiopathic). Several illnesses can cause the esophagus to dilate, leading to secondary ME. These disorders include obstruction of the esophagus due to foreign body (such as sticks, rocks, bones), narrowing or stricture due to scarring of the esophagus caused by trauma, cancers and other tumors, developmental problems, neurologic diseases, infections, inflammation, immune system diseases, hormonal disorders, and toxins.
Symptoms of Megaesophagus in Dogs
Signs can vary from patient to patient and can look similar to other diseases or disorders. Most often, pets with ME experience regurgitation of food or water. This is different from vomiting, as regurgitation does not involve any obvious effort to bring food up. Vomiting includes signs of nausea, salivation, stomach contractions, and retching. Regurgitation is effortless, with the pet tilting their head and neck downward, and the fluid and food (often foul-smelling) flow out onto the ground. Regurgitated food is undigested, often in chunks, without yellow bile from the stomach and intestines. Sometimes pets bring up only frothy fluid.
Additional symptoms include:
- Excessive salivation
- Bad breath
- Weight loss
- Ravenous appetite
Dogs and cats with aspiration pneumonitis due to ME may also have the following signs:
- Discharge from the nose
- Difficulty breathing
- Weakness, decreased activity, sleeping more than normal
Diagnosing Dogs with Megaesophagus
ME can often be seen on x-rays of the neck and chest. Some cases may require special contrast (barium) to be swallowed, which is a liquid that shows up on the x-ray. This special liquid can show an enlarged or dilated esophagus. Other imaging tests that can diagnose ME include endoscopy and fluoroscopy. Your vet may send the x-rays to a veterinary radiologist to be read and confirm the diagnosis.
Blood tests and urinalysis will be recommended to determine if there are any other underlying problems and help decide the best treatment plan. Special tests may be ordered that are specific for diseases related to ME such as myasthenia gravis, immune-mediated diseases, hormone disorders, or toxins.
Treating Dogs with Megaesophagus
ME is a serious and sometimes life-threatening illness. The outlook for improvement depends on the reason or cause of ME, secondary problems such as pneumonia, response to medications, and owner compliance and care at home. Some cases will resolve completely if the cause of ME is treated and the pet responds, while others are more complicated.
Treatment goals for pets with ME are to treat the underlying cause if possible, decrease regurgitation, prevent overdistention of the esophagus, maintain a good level of nutrition and weight, prevent or treat pneumonia and improve the dog’s quality of life. If your pet does not respond to treatment, has a poor quality of life and is suffering, humane euthanasia should be discussed and considered.
If your pet has ME, you will be a key part of managing their care and treatment. You will need to check their weight, note changes in appetite, behavior, how often they regurgitate, and monitor breathing. Share this information with your pet’s pDVM (primary veterinarian).
Give all medications as directed by your pet’s pDVM. Raise your pet’s food and water bowls so that gravity will help move the food and water through the esophagus to the stomach. A special chair designed for dogs with ME called the Bailey chair helps to support them in an upright position for feeding. It is suggested to keep pets in a sitting, upright position for about 10-15 minutes after eating and drinking.
Your pDVM will recommend an appropriate diet for your pet. Feed your pet small frequent meals throughout the day. In some cases, pets require the placement of a feeding tube to maintain appropriate nutrition and weight. This is done under general anesthesia and your pDVM and veterinary team will show you how to feed, flush and maintain the feeding tube.
When to Contact a Vet
If you notice any of the signs or symptoms listed above or your pet has previously been diagnosed with ME and is experiencing any problems, you should contact your pDVM (primary veterinarian).
Patients that inhale food, water, or saliva into their lungs need immediate veterinary care that often includes hospitalization, medications, and oxygen support.
If your pet has been diagnosed with ME, always follow their vet’s instructions regarding diet, medications, and activity. Talk to your pet’s veterinarian before making any changes.