MEGAESOPHAGUS

Esophageal Weakness

Urška Bergant Bertoncelj, DVM

“Megaesophagus in dogs is a condition characterized by a dilation or enlargement of the esophagus, which is the muscular tube that carries food from the mouth to the stomach. This dilation is often due to weakness or dysfunction of the muscles in the esophageal wall, making it difficult for food and liquid to pass into the stomach properly.”

Megaesophagus refers to either focal or widespread muscle weakness of the esophagus; it is categorized into congenital or acquired weakness. In the practice of small animals, this condition is mostly encountered in dogs, though it is occasionally seen in cats. The breeds most prone to this condition include Miniature Schnauzer, Great Dane, Dalmatian, Chinese Shar-Pei, Irish Setter, German Shepherd, Golden Retriever, Labrador Retriever and Collies. Rhodesian Ridgebacks are not a predisposed breed.

Congenital weakness is extremely rare. The causes or development of its occurrence are still unknown. It is suspected to involve a defect in the function of the vagal nerve (10th cranial nerve). This form is often suspected when problems start to appear while the animal is still young. At this stage it is difficult to diagnose, and it is necessary to wait for the animal to mature—especially if the problems occur sporadically and in a very mild form. The first sign noticed by owners is vomiting, which is actually regurgitation (this means the backflow of stomach contents back into the esophagus and also into the mouth; synonymous with reflux). The difference between vomiting and regurgitation is most noticeable in the straining of abdominal muscles, as regurgitation is a passive process without straining of abdominal muscles and there is no prodromal phase (warning loops such as tightening of lips, deepened breathing, etc.). The regurgitated material often contains a lot of thick mucus and is not yellow in color. Other symptoms may include weight loss, coughing, fever or nasal discharge accompanying pneumonia; in severe cases, swelling and deflation of a balloon-like area on the skin of the esophagus can be visible. Additionally, poor growth in young animals, increased appetite or complete anorexia, hoarseness and bad breath may be observed.

In cases of acquired weakness, problems arise due to neuropathies, myopathies, or pathology at the junction of neuromuscular pathways (e.g. myasthenia gravis). As with congenital forms, the main symptom is regurgitation, although some dogs may only present with a cough. Weight loss occurs if regurgitation is frequent.

In a veterinary clinic, while conducting a clinical examination of a dog, one might observe additional signs such as heightened respiratory sounds, muscle wasting, and particular attention should be given to assessing cranial nerve reflexes. The diagnosis is most easily made using radiographic imaging, sometimes concurrently with contrast imaging, which, by staining the pathways, reveals expansions. In brachycephalic breeds, smaller, more tortuous placements of the esophagus are normal and should not be confused with megaesophagus.

Currently, there is no effective medication for treating congenital weakness, but aids and methods for easing or preventing symptoms can help, attempting to prevent further expansion and aspiration of food into the respiratory system (which can cause aspiration pneumonia). Dogs are fed on an elevated platform where the dog must stand on its hind legs, thus positioning the esophagus as vertically as possible, with gravity assisting the passage of food directly into the stomach. This position should be maintained for at least 5-10 minutes after the dog has finished eating and drinking. An example of a device that enables such feeding is a special chair called a “Bailey chair”. It is also very helpful to feed smaller meals more frequently. Regarding the type of food, feeding cooked oat flakes is recommended, but it all depends on the individual casesome respond best to dry food (kibble), others to canned food; all based on a “trial and error” method.

For acquired weakness, it is important to determine the cause of the weakness. This includes various tests such as measuring antibodies for acetylcholine receptors (myasthenia gravis), serum cortisol (hypoadrenocorticism-Cushing’s disease), electromyography (generalized neuropathies or myopathies), thyroid profile (hypothyroidism), and antinuclear antibodies (systemic lupus erythematosus). If the cause remains unknown, then it is referred to as idiopathic megaesophagus, which is unfortunately also the most common. In this case, the therapy is the same as for congenital megaesophagus. Based on the de-

Susanne Neu

Diagnosis Of Megaphagus

One day our 12-year-old Rhodesian Ridgeback female began to cough, with food coughing up again and again. Since there was no improvement in sight, we consulted our veterinarian. After my description of the problem and a subsequent X-ray with contrast medium, the diagnosis was made quickly. Hanna has pneumonia caused by a Megaphagus.

The prognosis was frightening: approx. 14 days, then the dog will be starved to death. At home, we tried to keep Hanna upright while feeding so that the food can slide into the stomach. But with an older dog lady, it’s not easy. Not pleasant for a big dog and also exhausting for us.

After research on the Internet, we came across the Baileys Chair. We had to give it a try, we could not give up on our girl so easily. My husband built our saving chair in the basement within 2 hours. We put Hanna in, which she accepted without any problems and we started to offer her the food pureed and very liquid. She enthusiastically accepted it. On the 2nd Day she has already tried to climb into the chair by herself.

After the food, she gets puppy milk to rinse the oesophagus, which she likes to drink. We do this procedure 3 times a day. She has her old weight of 33kg again and the cough has become very rare. We are overjoyed! She is our old happy girl again.

Elke Lockert termination of the cause, drug therapy can be prescribed.

I met Jenga in May of 2008. After 3 bottles of wine, I decided to "go look" at him, ended up sleeping with him and he never left. Lol. Jenga was a rescue from Florida Ridgeback Rescue. Wherever he came from, then found on the side of the road, went to animal control, then to Ridgeback Rescue then to me....all within the first 7 months of his life. He was a mess. Then to add more craziness, I had just gotten a puppy (Kenji) a few weeks before meeting Jenga because I had just lost my Ridgeback Sire. The 2 of them became the best of friends. They were known as the KJ Duo. Kenji and Jenga. Jenga became the best sweetest, most lovable, cuddly, kissy, goofy, marmadukey boy ever and I was so glad that I got to be his Momma.

Fast forward to 2017, Kenji had gotten a rare form of anal cancer and I had to let him go. I reached out to my Breeder and ordered another puppy who I named Zumanii. Jenga and I went and picked Zumanii up and they quickly became BFF's. A week after Zumanii coming in, Jenga started not eating, then started to regurgitate whatever he did eat. He started losing a bunch of weight. We did all sorts of tests and couldn't figure out what was causing this. I started researching more and had saw an article on Mega E. We finally determined this was the cause. Mega E is really hard because it's a trial and error thing in what works and what isn't working. I started blending his food and had him eat on stacked crates. That worked for a little while but then I had to switch it up and started giving him raw food balls and then built him a "Bailey" chair where he had to sit in it for 30 minutes after eating upright. We had to do this 4 times a day. This worked for 6 months and finally one night, he let me go while we were sleeping. This was the absolute best way that could've happened.

I always said that Jenga was so goofy but at the end of the day, he was the smartest dog because he let me go on his terms and I didn't have to make that dreaded decision.

I miss Jenga every day along with Sid, Sire and Kenji. I still have Zumanii and he's my big loverboy and I'm so glad he lets me be his Momma!

In some dogs, the esophagus can narrow to normal width and perform its function. Even if the esophagus remains dilated, some dogs manage to maintain a good quality of life with dietary modifications and feeding methods. In other cases, the placement of a tube through the abdominal wall directly into the stomach (gastrostomy), through which the dog is fed, works well, although this does not prevent reflux.

In conclusion, while megaesophagus presents significant challenges, especially in its congenital form, there are strategies and interventions available to improve the quality of life for affected dogs. From specialized feeding techniques like using Bailey chairs to diagnostic tests for acquired weakness, veterinarians and pet owners can work together to manage the condition and alleviate symptoms. Although there’s no onesize-fits-all solution, tailored approaches based on individual cases can offer hope and comfort to both dogs and their devoted human companions. With ongoing research and advancements in veterinary medicine, the outlook for dogs with megaesophagus continues to evolve, offering optimism for a brighter future ahead.