Spotlight: Otitis Externa

Say whatsy whosie? Otitis externa is a fancy name for an infection of a cat's external ear canal. It affects 2-10% of all cats seen in a general veterinary practice, ranking second in the most common illnesses treated by vets. Some cats are more prone to it, and in those who get chronic ear infections 20-30% of cases are due to an unknown cause (idiopathic). Himalayan and Persian cats seem to be more prone to otitis externa, as do some diabetic cats.

To understand how to prevent ear infections, it's important to understand what causes them. Here's what you need to know:

Causes of Otitis Externa

By far, the most common cause of otitis externa is ear mites. They cause about half of all cases. Kittens are especially prone to them. If your cat's ears have a black discharge, ear mites may be the culprit. Ear mites can be treated with a number of over-the-counter remedies. A couple we carry are Ear Mite Remedy by Four Paws and Ear Rite Miticide by Lambert Kay. Other bugs that can cause otitis externa include chiggers (redbugs), ticks lodged in the ear canal, and mange (scabies).

Two other common causes of otitis externa are bacteria, dermatophytes (fungus) and yeast. These can set in if an initial infestation of ear mites is left untreated. Often, even if the mites are treated, the secondary infection may remain and require treatment by your veterinarian.

Other causes: thick or matted hair, excess wax buildup, a foreign object, a tumor or polyp, allergies, or an impaired drainage system. Cats prone to fighting may get injuries that can abscess and cause an ear infection. Feline papilloma virus may also cause them. A hot, humid environment can set up a perfect environment for pathogens to cause an ear infection in your cat.

In some cases, cats who have contracted the feline leukemia (FeLV) or feline immunodeficiency virus (FIV, also known as feline AIDS) may present ear infections as a symptom. If your cat has not been vaccinated against these diseases, a blood test will determine if she has contracted one of them.

Symptoms of Otitis Externa

Ear infections cause itching and pain for your cat. You'll probably see him shaking his head often or scratching at his ears. While cats often clean their ears as part of their normal grooming, excessive attention to the ears can indicate infection.

The infected ear may look red and swollen. As the infection progresses, you'll probably notice a foul odor. Sometimes there is a discharge. Some cats may wail when in severe pain.

Why Treatment Is Important

When properly treated, just about all ear infections are curable. While it may take several weeks and multiple vet visits, properly diagnosing and treating your cat's ear infection is well worth the investment.

If left untreated, an infection in your cat's outer ear will not only continue causing pain, but may spread to the middle ear. Infections there are much more difficult to treat, sometimes requiring surgery and a multi-week recovery period (and costing you much more in the long run). Even worse, the infection could become systemic and require an injection of antibiotic, followed by pills given daily at home until it clears up. Your cat's behavior in trying to scratch her ears or shaking her head may also break delicate blood vessels and cause more serious problems.

If the otitis externa is being caused by a foreign object, it can rupture the cat's eardrum. If the infections are chronic, the eardrum may become damaged and the ear canal close up, rendering kitty deaf. Because there are so many potential causes of otitis externa, it's important that your cat see a veterinarian as soon as you notice the symptoms.

Chronic ear infections can cause swelling that will progress to fibrosis and calcification of the ear cartilage that requires treatment with corticosteroids for up to a month. Secondary infections from a variety of bacteria can turn a mildly unpleasant situation into a serious medical condition.

What Treatment Involves

Your veterinarian will examine the cat's ear to see if the eardrum is still intact. If the infection is severe, the cat may need to be sedated even to perform the exam. A sample of the material in the cat's ear canal should be taken by the vet and examined under a microscope to identify the culprit. Knowing exactly what's causing the infection will determine which treatment should be used. There may even be more than one cause that calls for a multi-pronged treatment.

After an initial cleaning by the vet, you may need to clean the cat's ears twice daily with a medicated solution for a week or two. This usually involves holding the cat on your lap and squirting a small amount of the solution into the horizontal part of the ear, holding it closed for a few seconds as you massage it, then drying the ear with a cotton ball (not a cotton swab; it can push the material back into the ear canal) to remove dirt and any other material dislodged by the solution. You'll be able to hear the solution squishing around in the ear as you massage it. Proper care must be taken to avoid damaging the cat's eardrum while doing this.

Your cat will enjoy this about as much as you would enjoy having something squirted in your ear when it hurts, so it's recommended that you put a multi-folded towel underneath him so his claws will have something other than your thighs to grab onto. For particularly strong cats, you may need an extra person to help restrain him with a second towel, as he will try to push your hands away from his painful ear with his front paws. Wear some old clothes, as he'll shake his head once you've stopped massaging the ear, and any wax or discharge in the ear will fly all over you. After his treatment, you can reward kitty with a tasty treat. He'll be mad with you for a short time, but will get over it and soon be cuddling with you again once his painful ear has healed!

If the cause is allergies, your cat may need to receive regular therapy to treat the underlying allergy causing the infections.

In some severe cases, surgery may be required to open a closed ear canal. Your veterinarian will be able to advise you on this. Sometimes this procedure can result in deafness on that side for the cat.

Worth A Pound of Cure

While you can't ensure that your cat never gets an ear infection, some precautionary measures will help. First keep your cat indoors so he won't be getting into fights with neighborhood cats. This also lowers his risk of being exposed to parasites like mites or ticks that can cause ear infections, as well as the more dangerous FeLV and FIV diseases.

Regularly cleaning your cat's ears will also keep wax from building up there and possibly causing problems. One cleaner we carry is Earoxide Cat by Tomlyn. It's used similar to the way the medications are administered, as described above, except that you don't need to dry the ears with the cotton ball after using it.

Ear Dr. from PetAlive is an all-natural treatment with herbs and olive oil. Keeping some on hand may be a good first line of defense if kitty starts scratching her ears a lot, but it won't substitute for an accurate diagnosis by a veterinarian.

The Bottom Line

If your cat is showing symptoms of an ear infection, get to the veterinarian. It may be something simple, or it may be serious. Waiting to seek treatment will not only cause your cat to suffer longer, but could drive up your cost for treatment exponentially. Ear infections are not like that noise your car makes that you can turn up the radio to drown out!

Purrs!