By Leonard D. Jonas, DVM, MS, DACVIM Wheat Ridge Veterinary Specialists www.wheatridgeanimal.com
Ear infections (otitis) are a relatively common problem for dogs. Most of the time, they can be easily treated and cured. However, in some cases they can become chronic and recurrent. In these circumstances, more complete investigation into the cause and longer-term treatment plans are required.
Causes of acute otitis include foreign objects such as plant material and stones, allergies, parasites, and water in the ear from swimming or bathing. Chronic and recurrent otitis can be caused by allergies, hormonal diseases, tumors, immune mediated diseases or incomplete/inadequate treatment of an acute infection. The underlying problem changes the micro-environment in the ear, allowing the development of bacterial and yeast infections.
Certain breeds are more predisposed to infections. Cocker Spaniels, Bassett Hounds, and other floppy-eared breeds are at higher risk because of increased humidity in the ear canals when compared to dogs with erect ears. Dogs such as Poodles with excessive hair growth in the canals may also be predisposed to developing ear infections.
Allergies are by far the most common cause of chronic ear infections. Besides treating the infection component, the underlying allergy must be addressed or else the infection will continue to recur.
Ear infections can cause great discomfort to your pet. Typically the symptoms include pain, redness, head shaking, scratching at the ears, drainage, and a foul odor coming from the canals. On occasion the infection may move to the middle or inner ear. In these cases the symptoms may include deafness, inability to blink, tilting of the head to the side of the infection and loss of balance, circling, rolling, or inability to stand.
The diagnosis of an ear infection is based on the clinical signs the pet demonstrates, the physical examination by the veterinarian, and the use of several diagnostic tools. In most
cases the veterinarian will look down the ear canal using an otoscope. This allows the vet to assess the amount of debris and inflammation present, inspect for foreign objects, ear mites, ticks and tumors, and to evaluate the ear drum to see if it is intact or ruptured. Another diagnostic tool is cytology. This involves taking a swab of the ear debris and examining it under a microscope for the presence of mites, bacteria, and yeast. This test is of great importance in the selection of proper medications for treatment of otitis.
In many acute otitis cases, a 2-3 week treatment course with a topical drop or ointment placed into the ear canal may be all that is necessary. If a foreign body, a tick, or a very heavy buildup of debris is found, sedation will likely be required to remove the irritant or to allow a thorough cleansing. When there has been a chronic infection, ear drops and ointments are usually inadequate to clear the infection. In these cases systemic medications (oral pills and capsules) will be necessary. Antibiotics are used for bacterial infections and antifungals for yeast infections. Glucocorticoids such as prednisone or dexamethasone are often included to reduce the amount of inflammation in the ear. Therapy may be required for many eeks to get the ear canals back to normal.
Pet owners can help their pets avoid ear infections by practicing preventative care. Watch your dog carefully for scratching at the ears or shaking the head. Check the ears for redness, odor, or the presence of debris. A weekly ear cleaning at home with a veterinarian-recommended cleansing solution can minimize or prevent infections. Do not use cotton-tip applicators in the ear canal, as they tend to push debris further into the canal rather than lifting it out. Good preventative ear care can save your dog a lot of discomfort. Contact your veterinarian if you determine there is a problem.
