Otitis Externa in Dogs
By Dr. Julie Woodman
One of the most common conditions we see dogs for is ear infections. In fact, a study done by Nationwide Pet Insurance listed them as the second most common medical conditions that prompted veterinary visits. So it is important to have an understanding of this malady that affects so many of our canine friends.
What we commonly refer to as an ear infection goes by the term otitis externa, meaning inflammation of the external ear canal. In some cases the ear pinna (flap) and/or the middle ear may also be involved.
It is important to have an understanding of the many causes of otitis externa. Many different factors are involved in the development of otitis externa. These include predisposing factors, primary causes and perpetuating factors.
Predisposing factors alter the ear canal’s environment, thus allowing secondary bacterial and yeast infections to occur. Examples of predisposing factors include: floppy ear, narrowed ear canals, excess hair in the ear canal, frequent swimming and mechanical trauma to the ear canal from overzealous cleaning of the ear canal.
Primary causes are conditions that directly cause inflammation in the ear canals, such as: parasites, allergic skin disease, foreign bodies, masses in the ear canal, and hypothyroidism.
Perpetuating factors prevent resolution of the ear inflammation or worsen an existing issue. Examples of perpetuating factors are: bacteria and yeast infections, inflammation of the middle ear (otitis media) and progressive or persistent changes in the ear canal such as swelling, scarring or mineralization.
The symptoms we frequently see are discharge and odor from the ear, redness and swelling of the ear, rubbing or pawing at the ear or shaking of the head.
When a dog comes into the clinic with these complaints a full ear exam is performed by a veterinarian. An otoscope is used to look inside the ear to evaluate the amount of debris and exudate in the ear, to look for changes in the ear canal and to evaluate the eardrum (tympanic membrane). The ear canal is swabbed, and the material collected is examined under a microscope to look for bacteria, yeast and ear mites. In more serious or chronic cases, and ear swab may be submitted for bacterial culture.
The goals for treatment of otitis externa are to remove the debris from the ear canal, relieve inflammation, and resolve infection. It is also vital to control predisposing and perpetuating factors and treat the primary cause. Most often medications are used in the ear directly. Common medications applied to the ear include cleaning agents, antibiotic and antifungals to treat the infection, and corticosteroids to help relieve the itching and swelling. In more severe cases oral medication may also be prescribed. Specific treatment for any underlying causes is also important.
In the majority of cases otitis externa is easily treated, but in cases with certain underlying causes, like allergies, it may not be cured and instead will be controlled and managed. In certain extenuating circumstances surgery may be required to relieve the dogs pain and resolve the infection.
If you notice any of the symptoms above in your dog, please call our clinic and make an appointment. We want to help your dog to live a happy, healthy pain-free life as long as possible.