Dog - Megaoesophagus or Oesophageal Dilation

What is megaoesophagus?

This condition results from dilation or increase in the size of the oesophagus (gullet) which connects the mouth with the stomach.  The increase in diameter of this tube results in an inability to contract and push the swallowed food into the stomach.  In consequence the food accumulates in the gullet and causes vomiting or more accurately, regurgitation of the meal, a variable time after the dog has eaten.  Fluids usually run down into the stomach but in some cases these too can be regurgitated some time after drinking.

Are some breeds more prone?

The condition is not uncommon in dogs and appears to be congenital (present from birth) in some.  There appears to be a familial predisposition in German Shepherd dogs, Great Danes and Irish Setters.  Some forms of the condition appear to be truly congenital and these will be evident shortly after weaning.  Due to its variety of causes megaoesophagus can, however, occur in dogs of any age.

What are the signs?

Frequent vomiting (regurgitation) after eating, together with a failure to thrive, are the main signs.  Because of the frequent regurgitation the animal often has a chronic pneumonia.  This will result in coughing and sometimes a mucopurulent (thick, pus-like snot) nasal discharge.  Feeding difficulties may also be observed.

What are the causes?

The congenital form may or may not be hereditary.  Other causes can include central nervous system disorders as well as neuromuscular diseases such as myasthenia gravis or systemic lupus erythematosis.

Inflammation of the oesophagus can also result in this unfortunate condition.  This can be due to infection, oesophagitis, or simply as a result of severe scalding due to drinking too hot a liquid.

Damage following an oesophageal obstruction, e.g. a bone in the throat, can result in megaoesophagus due to damage to the gullet.

How is the condition diagnosed?

The condition can often be suspected on the history particularly if it is noted that there is improvement if the dog is fed with the head in a raised position.

Once a tentative diagnosis has been made it is usual to undertake fairly exhaustive laboratory and diagnostic procedures including endoscopy, diagnostic imaging (including x-rays with barium swallows), and diagnostic ultrasound, etc.

What is the treatment?

Careful management is paramount.  We will go through this step by step since feeding presents less problems if it occurs in an upright position, either with the food bowl raised on a stool or on steps, etc.  Antibiotics and other drugs are sometimes prescribed on a long term basis in order to minimise complications such as pneumonia.  Repeat ultrasound scans or x-rays together with other tests are also often necessary.

Will treatment cure my dog?

The condition is frequently incurable although careful management will allow the dog to lead a relatively normal life.  However this can be expensive both in terms of time and money and we are more than happy to discuss all these aspects with you.

Megaoesophagus in puppies that has been present from birth sometimes resolves as the puppy reaches adulthood.  Unfortunately this cannot be guaranteed.