Several factors contribute to a pet’s outer ear disease (otitis externa). These are broken down into predisposing, primary, secondary, and perpetuating factors.
Predisposing factors are often genetic or conformational, such as the pendulous ear flaps of certain breeds (for example, American Cocker Spaniels or Bassett Hounds). These are factors present in healthy dogs that may nevertheless predispose them to ear disease in the future or complicate the management of ear disease.
Primary factors include disease states such as allergies, endocrine disease, parasites (such as ear or skin mites), and neoplasia (tumors). These are factors that can cause ear disease by themselves by directly affecting the ear canal's skin lining or obstructing the ear canal's normal biological functions.
Secondary factors can include infection with hard-to-treat pathogens, such as Pseudomonas or Malassezia. Secondary factors require management in addition to treating the underlying disease.
Perpetuating factors are changes to the ear following a previous disease that may also complicate management. These include changes to the ear canal wall leading to narrowing (stenosis); disruption of the eardrum (tympanic membrane); changes to the normal bacterial and fungal inhabitants of the ear canal; and infection of the middle ear (otitis media). Perpetuating factors often contribute to treatment failure and must be managed along with primary and secondary factors. Sometimes, it is not possible to manage an ear with chronic progressive change, and surgery may be required.
If the underlying causes of ear disease are left untreated, more severe signs can develop. These include increasing discomfort, itch, hearing loss, and neurological disease (head tilt, loss of balance, ascending infection). Early diagnosis and treatment are the best way to reduce the risk of this occurring.
Your veterinary dermatologist will take a thorough history of your pet’s signs to determine the most likely underlying cause of the ear infection. This may include but is not limited to performing cytology, culture, sedated or anesthetized ear examination, deep ear flushing, biopsy, or CT scan. Your veterinary dermatologist will recommend the appropriate course of treatment based on the underlying disease, type of infection, and the severity of the effect on the ear.
Contact our office today to schedule an appointment for more information on what a veterinary dermatologist can do for your cat or dog.
Even healthy dogs and cats can benefit from routine ear cleaning. We recommend gentle ear cleaners with little to no alcohol for safe and effective ear cleaning. NEVER place any object (cotton ball, cotton-tipped applicator, paper towel) down into your pet's ear, as this can be irritating and painful in addition to being a potential foreign body or possibly disrupting the eardrum. We recommend soaking a cotton ball with an ear cleaner and squeezing out the contents of the cotton ball into the external opening of the ear canal. Gently palpate the ear canal below the opening with your fingers for about 30 seconds. You may place a dry cotton ball at the opening of the ear canal and then let your pet shake out the excess cleaner.
Always follow directions on any ear medications dispensed by your veterinarian. Continue to apply medications even if signs of ear infection have improved. Routine maintenance therapy is often the key to preventing flare-ups.
If you notice signs of an ear infection, especially one that is not responsive to therapy, please schedule an appointment with your veterinary dermatologist.