Megaesophagus in Dogs

Question: Hi Dr. Richards,

We have reason to suspect that one of the pups in our 4 wk. old litter of Portuguese Water Dogs may be afflicted with Megaesophagus. We first noticed that the smallest puppy of the lot, who we had been topping up regularly with bottle feeding, began having problems swallowing and holding down food when we started the litter on some semi solid food about a week ago. Can you tell us is there is any way to may an exact diagnosis of this particular problem or what other possible causes may be producing these symptoms? Also, if it is megaesophagus, what if any treatment is prescribed and is there any research being done at ways to rectify this problem. RThanks so much.

Toni & Tris

Answer: Toni and Tris-

At this age, the most likely problem is a persistent right aortic arch compressing the esophagus and preventing solid food from passing through. This problem typically shows up about the time a puppy is weaned, since liquids can make it through the esophagus with no problem.

The right aortic arch (an embryonic structure) crosses over the esophagus, so if it develops instead of the left aortic arch, the esophagus is compressed.

It is important to try to fix this problem as quickly as possible because the damage to the esophagus that occurs as food tries to make it through the obstruction may be permanent. The only cure that I know of is surgery to remove the constriction from the aortic arch. If there is already damage to the esophagus the dog may require soft foods or small frequent feedings for life.

It is not uncommon for puppies with this problem to develop inhalation pneumonia, so watch for signs of this.

There are other reasons for esophageal strictures in puppies and megaesophagus does occur congenitally. It is important to quickly sort through all these possible causes, so consider asking your vet for referral to a specialist quickly, if that is necessary.

Mike Richards, DVM 6/28/2000

Megaesophagus prognosis - Welsh terrier

Q: Our 9-month-old Welsh Terrier male has been diagnosed with megaesophagus since babyhood. His vet said that the condition might correct itself, at least to some extent, by one year of age. Careful feeding, careful choice of food and regulation of his exercise, along with quick action when he shows signs of pneumonia from aspirating food or vomit have kept him alive so far. Though he's had many "bad days," he tries to be a normal, active puppy. He is stunted in size (He's probably half the size he should be at this age.), but not in personality or will to live! Our vet thinks that neither drugs nor surgery can be used to improve his condition. How long do dogs with this problem usually live? Is there anything else we can do for him?

A: John- I am sorry for the delay in replying to your question. Unfortunately, I don't have any more information for you. The treatment protocol for megaesophagus is what you have stated already - careful feeding, proper choice of food and quick treatment of secondary problems associated with the regurgitation which in most cases is aspiration pneumonia. There is a drug available in Canada (cisapride) which may be helpful in some cases but this is not approved for use in the US that I know of. Surgery is not very beneficial to correct the condition so most of the cases are treated medically. It would be hard to tell you how long your puppy will live. Some dogs respond well to medical management but others respond poorly despite the owner's commitment and compliance. Aspiration pneumonia is the major cause of death in these dogs. Because of this, prognosis is considered guarded.

Most dogs with congenital megaesophagus die within the first two years of life, usually from aspiration pneumonia. The things you are doing are the right things to do and I do not have much other advice.

Mike Richards, DVM

Megaesophagus and medication - German Shepherd

Q: My brother and sister-in-law have a five year old German Shepherd (Tosh). He was dignosed with Megaesophagus in his first year. It has been under control for four years with few problems. Within the last month he has been vomiting late at night - sometimes up to eight times in one evening. He was given Reglan and Carasete/Sucralsate - which did not help - they thought that perhaps it was not getting into his system because he was vomiting so much. He was then given Centrine which did stop the vomiting. However, the vet hasn't had any success in trying to determine was is causing the vomiting. Can you provide any insight or suggestions as to where to go from here? Any help will be greatly appreciated by Tosh's family and vet. Thanks.

A: Sandy- Medications are not all that effective for megaesophagus when there is not a discernible underlying cause. Pyridostigminee bromide (Mestinon Rx) is used when myasthenia gravis is the initiating cause of the megaesophagus. Cisapride (Propulsid Rx) has been advocated for use in megaesophagus but the results are variable. I have seen a reference to the use of nifedipine (Procardia Rx) for megaesophagus but it was pretty old and I haven't seen much more about it so I have to wonder how successful it was. Still, if you don't have much to lose by trying it there probably isn't any reason not to.

Mike Richards, DVM

Megaesophagus, ring anomalies in Boxer puppies

Q: We have a litter of eight Boxer pups, three of whom were recently diagnosed by Virginia Tech Vet School with megaesophagus and put down. The other five are currently being fed standing up, are gaining weight, are playful and have some regurgitation. Do you have any suggestions for treatment, medication, etc. for the other five? The pups are going on four weeks of age. Could you give us more information on ring anomalies. The aortic arch as a contributing factor has been ruled out. Cheryl

A: Cheryl- I am sure that Va Tech ruled out the ring anomalies -- these are all the result of fetal circulatory channels that should degenerate at birth but sometimes remain as a fibrous band that entraps the esophagus in a "ring" of tissue and makes it impossible for solid food to pass beyond the ring. When puppies are weaned they start to regurgitate because the food can't make it to the stomach. This causes the esophagus to swell in front of the ring and megaesophagus occurs. It is treatable by cutting the fibrous band and if caught early the esophagus will often return to near normal size. If missed long enough, the esophagus may be too damaged to repair itself.

Mike Richards, DVM

Megaesophagus or Ring Anomaly - Rottie

Q: We just bought a Rottweiler for Christmas. The puppy could not keep food down, eating vigorously and then regurgitating constantly. We took dog to vet and they X-rayed.

He has megaesophagus. The vet said he has never heard of a puppy having this. The xray showed the esophagus larger than even an adult dog with megaesophagus.

The Vet suggested there is nothing we can do except try different methods of feeding like small portions 3 to 4 times a day, and feeding very little. Try soft food, that didn't work, tried hard food, tried combination of soft and hard. He also said hold him upright for 5 minutes after eating.

None of these things seem to work very well, although he is getting some nutrition. He is still pretty thin and seems to be asperating a little. He also is very hungry. Very hungry all the time and he eats so fast. None of the food seems to satisfy him.

He was the runt of the litter. How can we get him to slow down eating and is there anything we can do for him so he is not so hungry all the time?

A: In a puppy this young it would be very important to rule out a vascular ring anomaly constricting the esophagus. This is a situation in which the fetal blood vessels are still present when they should not be. The most common form of this is a persistent right aortic arch, but there are other possible ring anomalies. The vessel passes over the esophagus and captures it between the persistent aortic arch and other structures, constricting it. This can be cured surgically if many cases. In some cases, the esophageal motility is permanent impaired and it is necessary to feed liquid or semi-solid meals from a standing position for life.

Please ask your vet if he or she can check for the ring anomalies and if not, consider referral to a cardiologist or veterinary referral center (like a vet school) where these can be rule out.

Mike Richards, DVM

Megaesophagus? German Shepherd

Q: Dear Dr. Mike- I have a 2 year old german shephard, Hannah. She appears to be in good physical shape, acts normal and shows no signs of illness. However, she seems to be having trouble drinking water and eating at the same time. If she has food and drinks afterward she just opens up her mouth and all the food/water she has taken in comes right back up. Sometimes there is mucous in the vomit, too. If we give her only the food, she is fine. However, even after a couple hours after she has eaten, and even limiting her water intake, she will still vomit up what is in her stomach. What could cause this? As I've said, she shows no other sign of sickness. She is playful, her eyes and nose are clear, and no signs of diarrhea or listlessness. We feed her dry food (dog chow) and water and very little table scraps or dog treats. (especially since all this started). She has done this off and on since we've had her, but recently it has just gotten worse. When we told our vet before (its been about a year), he just thought it was something she ate. Now it seems it has been going on for a month or so. Help!!

A: I don't know what it is about the name Hannah and German shepherds, but it has been a really bad combination in my practice. I see a couple of very nice shepherds named Hannah with the some of the most frustrating problems. I just cringe when someone tells me they have a German shepherd named Hannah.

The history you give makes me worried that this bad luck will continue. I would be very very worried about megaesophagus with the signs you are seeing. This is a condition in which the esophageal muscles lose their strength and the esophagus dilates to a much larger size. Usually dogs with this condition regurgitate food as well as water but I have seen at least one other dog that started out just regurgitating when it drank water. Sometimes the enlarged esophagus is visible on plain X-rays of the chest but often it is necessary to use some kind of contrast medium like barium to make the enlargement visible.

There are other possible problems like esophageal diverticuli, hiatal hernia, esophagitis, pylorospasm, esophageal tumors and probably others. In addition, there are about thirty disorders that can cause a secondary megaesophagus problem.

With the signs worsening, it is time to talk to your vet again. Let him or her know that you are very worried and want to find the cause of this problem. If your vet still doesn't take you seriously, ask for referral to a specialist. This will usually stimulate a veterinarian to review a case or to honor the request immediately. Either way, it is likely an answer will be found. If your vet balks at the request and still doesn't seem interested in seriously pursuing a diagnosis you will know it is time to look for a new vet.

Mike Richards, DVM

Megaesophagus in Scottish Deerhounds

Q: Dr. Mike, I have a 3 1/2 year old Scottish Deerhound bitch that had a litter of pups last year. One of the pups has megaesophagus. Is this a genetic problem? Should I not breed the bitch again? Should I breed her to another stud? I have done all the other genetic testing I can think of, is there a test for this?

Thanks for your input.

A: It is pretty hard to answer your question directly. According to Barbara Watrous, writing in the book Small Animal Practice, megaesophagus is known to be inherited in Wire-haired Fox Terriers and Miniature Schnauzers. It seems to occur more frequently in Great Danes, German Shepherds, Labrador Retrievers, Shar Peis and Irish Setters. It can occur in cats, as well. Siamese cats are a little more likely to be affected. The problem can be inherited, but Scottish Deerhounds are not reported to be among the breeds with a predisposition.

Megaesophagus can be caused by other congenital deformities, such as vascular ring anomalies (a defect in which the esophagus is trapped by residual fetal vessels and food can not pass through it properly).

Megaesophagus also occurs secondarily to a large number of primary diseases.

It would be a good idea to find out when the megaesophagus showed up and whether or not it appears to have been caused by some other problem or if it seemed to occur spontaneously. That would give you a better idea of what problem you might be dealing with and allow an estimation of the heritability.