Dog - Tonsillitis

How common is tonsillitis in dogs?

Since they have tonsils, dogs also have tonsillitis.  It is fairly common particularly in small breeds of dogs but less common in large dogs.

What are the tonsils and what do they do?

The tonsils can be thought of as lymph nodes (lymph glands-like the glands under the lower jaw).  There are two of them, one at each side of the back of the throat.  When they are normal, they are not easily seen because they reside in crypts (pouches).  Like lymph nodes, their job is to fight infection.  When they are doing this, they often become infected themselves and will enlarge.  Swollen, red tonsils that are out of their crypts are easily seen at the back of the throat if the dog will permit the mouth to be opened sufficiently.

How did my dog get tonsillitis?

There are certain conditions known to cause tonsillitis.  Chronic vomiting, a chronic productive cough, and chronic disease in the mouth will allow bacteria to infect the tonsils.  The main cause of chronic oral disease is tartar on the teeth and the infection that is associated with it (periodontal disease).  Occasionally, primary tonsillitis (no underlying cause) will occur; this is almost always in small breeds of dog.

What are the clinical signs of a dog with tonsillitis?

When the tonsils enlarge, they are usually quite painful.  This causes the dog to gag, as if something is in the throat, or to make exaggerated swallowing motions.  Some dogs appear to be licking their lips repeatedly.  Most affected dogs are reluctant to eat because of the pain associated with swallowing.  They may appear hungry, go to the food bowl but refuse to eat.  Many dogs with tonsillitis are not as active as normal, but they usually do not have a raised temperature.  This is the one characteristic that differs markedly from people with tonsillitis.

How is tonsillitis treated?

If an underlying source of the infection can be found, it must be treated.  Appropriate antibiotics are given for 2-3 weeks in an effort to rid the tonsils of infection and to treat any other infections that may be present.  If dental disease (periodontal disease) is present it must be treated.

What about a tonsillectomy?

A tonsillectomy (removing the tonsils) is not the first approach to treatment but can sometimes become necessary if there is poor response to treatment or if tonsillitis becomes a recurring condition.  This is more likely to happen in small breeds of dogs.

Is this contagious to other dogs or to humans?

Most cases of tonsillitis are caused by bacteria that normally are found in the mouth of dogs and humans.  Therefore, it is not contagious unless it is caused by an unusual bacterium.

Can a Streptococcal throat be associated with dogs?

Streptococcus pyogenes, the cause of 'strep throat' in humans does not cause tonsillitis in dogs or cats.  However, dogs and cats can acquire a transient infection with this bacterium when they are in contact with a human with a streptococcal throat infection.  Although they do not get the infection, they may harbour the bacterium and pass it on to other people.  Therefore, it is suggested that dogs should be treated when family members have streptococcal throat infections, especially if recurring infections occur in the household.