Saturday, August 3, 2013

                     Ear Infections in Your Pet and What You Need To Know

Normal healthy ear
Ever had an ear ache? ....An ear ache so bad, you see stars or really interrupts your life. Maybe you've had a long term ear ache that makes you grumpy or worse.

Dogs and cats get ear aches too. They don't like ear infections either.

Ear infections of the outer ear, or external ear canal,  is a very common problem that is dealt with by all small animal veterinarians.  The condition may be acute and develops quickly, or it may be a chronic or frequently recurring problem.  

Infected, inflamed ear

Signs of ear infections, or scientifically speaking, Otitis Externa , are easy to recognize and include head shaking, scratching at  the ears, red and swollen ear canals and ear flaps, pussy or waxy discharge, and pain.  Many animals will cry out when touched around the ears or head and some may become aggressive and try to bite.  Of course, punishment is uncalled for when an animal bites out of pain, rather, the compassionate response is to seek veterinary treatment for the pet.

Why does an animal develop otitis externa?  Otitis externa is not a primary disease ,
rather, the inflammation and pain is a response to some other underlying problem
that must be identified.

An animal may have "anatomical factors" that contribute to the development of the condition.  These are usually breed related and include small or narrow ear canals (such as in Shar-Peis), excessive hair in ear canals (poodles, Lhasas), and long, pendulous earflaps (Bassett hounds).

Primary causes of otitis externa include parasites such as ear mites (very common
in cats) or foreign bodies.  The most common primary cause of otitis
externa is allergies, which can be either to inhaled substances (atopy) or food allergies.

Perpetuating factors
increase the severity of the condition and play a major role in
chronic or recurrent otitis externa.  Perpetuating factors include bacterial, fungal, and yeast 
infections of the outer ear.  And "otitis media", which is inflammation/infection of
the middle ear, is often a source of constant reinfection of the outer ear.  One of the
most significant perpetuating factors is ear canal hypertrophy (thickening), which
may become so severe as to completely close off the outer ear canal and make

medical treatment of the ear near impossible. Before that happens, your veterinarian
should point this narrowing out to you and suggest medical or surgical intervention.

The worst way to treat an animal with chronic or recurrent otitis externa is to just keep applying antibiotic eardrops on an on-going basis and ignore the underlying and perpetuating factors that are involved.  Ear medications do play an important role in treating otitis externa but overuse will lead to the development of resistant organisms and a worsening of the otitis.   

Diagram of normal ear

 Treatment of ear infections must be individualized for each patient and must address the
underlying, predisposing and perpetuating factor that are present.

Treatment options include ear cleaning or flushing, culture and sensitivity, ear medications for infections, and or surgery. The two most common types of surgery are lateral resection of the external ear canal and ear ablation. Perhaps another blog can go into more detail about these procedures. Give me 20 dogs with ear canal issues bad enough for surgery and 19 of them will get the lateral resection of the external ear canal, and the 20th dog will get the ear ablation.

A typical case of a dog or cat with an ear infection would get a culture and sensitivity before the ear is treated. If is impossible to say for sure whether the ear is infected with a bacteria (or multiple bacteria), a fungal infection, complicated by mites or a yeast infection. Often the results come back as multiple causes. It is even more difficult to guess at the correct treatment until the test results are returned. Which antibiotic? Will an antifungal help?

After a C&S is taken, the ears are usually deep ear cleaned to flush out as much debris as possible. Then an antibiotic , both topically and orally is given. The owner is informed that one or both antibiotics may be changed for a more effective treatment once we know what will kill the offending organism.

If an infection is treated properly and diligently, the future maintenance is very easy and not expensive. If you do not treat the ear completely until the ear contains no disease, the ear infections tend to reoccur and usually results in the
 need for surgery.

At the first sign of ear trouble for your pet, please take him or her to your trusted veterinarian and together form a treatment plan that will minimize future infections.

The Providence Veterinary Hospital Blog is a publication of Peter Herman, VMD, at the Providence Veterinary Hospital, 2400 Providence Ave. in Chester, PA. Contact Dr. Herman at 610-872-4000 or visit us at