Ear Infections

By Dr. Christina Britto

Shakespeare, a 3-year-old Cocker Spaniel, came into my office shaking his head excessively. A sour scent was coming from his ears. His physical examination revealed two red, inflamed ears covered with yellow discharge and he was diagnosed with otitis externa, or inflammation of the external ear canal.

CAUSES & SYMPTOMS
A dog’s ear is an intricate organ that consists of the external, middle and inner ear. The external ear is made up of the pinna (or flap) and the vertical canal, which then takes an abrupt turn into the horizontal canal. The horizontal canal cannot be seen without an otoscope in the vet’s office and is the source of most of the earwax. The middle ear is divided from the external ear by the eardrum, and it houses several facial nerves. The inner ear lies closer to the skull and contains nerves to maintain balance and hearing.

Ear infections occur secondary to inflammation of the ear canal. The most common reason for inflammation of the ear is allergies. Hypersensitivities to fleabites, certain foods or environmental allergens can manifest in the ears. Other sources are mites, foreign materials (grass awns, sand or water) and some metabolic diseases (hypothyroidism). Bacteria and yeast normally exist in the ear canal; however, inflammation causes them to multiply creating a full-blown ear infection that requires treatment.

We most commonly see ear infections in breeds prone to allergies, and those with large, pendulous and hairy ears. These are Golden Retrievers, Labs, Cocker Spaniels, Springer Spaniels, Cavalier King Charles Spaniels and Poodles. Breeds who spend a lot of time swimming will also get frequent ear infections due to moisture entrapment in the ear canal. Twenty percent of all dogs in the U.S. are affected by otitis externa.

The most common signs that your dog has an ear infection are head shaking or scratching with their hind legs at red, inflamed and malodorous ears. Dogs with erect ears will sometimes tilt the ear downwards when affected. If the middle or the inner ear are affected, they can exhibit neurological signs like head tilt, bizarre eye movements, facial paralysis, dry eye or deafness.

Sometimes a hematoma, which is blood accumulation in between the cartilages, forms on the earflap. This makes the ear look large and puffy and happens after serious head shaking. This problem is usually resolved with surgery.

DIAGNOSIS & TREATMENT
Your veterinarian will use an otoscope to fully examine the inside of the ear. A sample of ear smudge can be evaluated under the microscope to help determine which medication is appropriate for treatment.

Repeat ear infections might call for an actual culture of the ear, which will be sent off to a lab and takes a few days for results. This test reveals exactly what organism is causing the infection and the best medication for treatment. Some severe cases might require sedation for full examination, and even tests like X-rays, CT scan or MRI to evaluate the middle and inner ear.

The basis of treating ear infections is keeping the ear clean and using an effective medication. Your veterinarian will determine the appropriate cleansing solution and medication based on the organisms seen in the ear and the state of the ear canal. Your vet will demonstrate the best way to flush the ears at home and suggest the frequency. I recommend using the bottle to flush the solution throughout both canals of the external ear, then massaging the ear base to break up the debris, and allowing the patient to shake his head.
It is not safe to put Q-tips down a dog’s ear (just like our own), but you can take a cotton ball to then wipe the outside of the ear. After the ear is dry, the medication should be applied. For serious infections, oral medications are prescribed, like antibiotics or steroids. And for advanced, severely debilitating ear infections, surgery might be the only option.

Your veterinarian will usually recommend a recheck in two weeks to ensure adequate healing of the ear. In some cases, further tests need to be run and the medications need to be changed for healthy ear success.

Avoiding ear infections in the first place is best! I recommend flushing your dog’s ears weekly at home with a veterinarian recommended product. Routine flushing allows a good look at the ears regularly and gets your dog used to ear handling, so he does not get angry with his doctor. There is also a drying flush available for avid swimmers and bathers. Routine visits to the vet are important for thorough evaluation of the ear canal, and if an ear infection is diagnosed, follow-up appointments are key.

Ear infections are one of the most common problems seen in the vet office daily, and can cause a lot of discomfort. However, with preventative flushing, consistent monitoring and diligent treatment, our dogs can have healthy, clean ears.

Symptoms to Watch
» Head shaking or scratching
» Red ears and sour smell
» Discharge in ear canal
» Droopy ear and head tilt

Dr. Christina Britto practices at the Brentwood Pet Clinic in West Los Angeles and has an interest in surgery and pediatrics. She shares her home with a mini Poodle named Sophie.