Pet Vet: Constant cough is hard to diagnose

September 22, 2014

Barley Boy was one of the lucky few older dogs at the local animal control facility. He was adopted. It was estimated that he was about 9 years old, and the guess was he was a mixed breed terrier. His new family has been caring for him for almost four months and he fits in very well in his new digs.

He does have one ongoing problem though one that he cannot seem to shake. His caretakers are not only frustrated but worried a bit as well. Barley Boy, aka BB, has a persistent cough.

Anna, BBs adopter, has taken BB to his veterinarian on three different occasions, starting just four days after he was adopted. Each time, the presenting complaint was BBs persistent cough. Because of his history as a dog from the animal control service, BB was initially treated for 10 days with an antibiotic, under the assumption that he had contracted "kennel cough."

Anna reports there was little if any improvement, and she returned BB to his veterinarian about three weeks into his new life. Anna was again given an antibiotic, a different one, to be used for two weeks.

Anna was not sure if she was being hopeful, but she did think that BBs cough lessened with the second course of antibiotics. It did not, however, disappear. A third visit to the veterinarian ensued, two months into BBs new life, still dealing with a cough. This time, BB was prescribed a cough suppressant and yet another antibiotic.

His cough greatly improved, making Anna, and I suspect BB as well, quite happy and relieved. Anna still harbored some concern because she was never sure what was causing BB to cough and her concern heightened when he recently began to cough again.

I would like to commend Anna on her inquiry as it contained a very good history of BBs problem, which makes my guessing a bit more educated. The first thing we need to realize with a coughing patient is that a cough is a symptom, a result of some type of insult to the respiratory system.

This system starts with the nose and mouth, continues down the throat through the trachea (windpipe), and down into the lungs via the main bronchi and bronchial tubes. An insult from the throat on down can lead to a cough. The list of possibilities is very long and especially so in an older dog like BB.

Annas concern that we do not know what caused/is causing BBs cough is paramount. We need to strive for a definitive diagnosis and the first step after a good physical examination should be imaging the respiratory tract.

This is done by taking pictures (radiographs) of the chest and possibly the throat. With these images, we can determine if there are any abnormalities visible that might be causing BBs cough.

Beyond radiographs, we may need to perform what is termed a trans-tracheal wash on BB. This is a procedure in which we flush some sterile fluid into BBs bronchial system and collect some back for analysis and culture for bacteria. This can be a very rewarding tool in trying to diagnose a cough.

I would also recommend a heartworm test for BB, as this parasite occurs in part of the vascular system associated with the lungs and causes coughing.

Again, there are many possibilities as to the cause for BBs cough. We must do everything we can to positively identify the underlying cause in order to affect a potential cure.

I have touched on some of the testing needed and there may be more. Obviously, antibiotics are not the sole solution.



Associated Press