Ear infections can cause uncomfortable symptoms and may recur. In this blog post, our Torrance vets discuss the impact of chronic otitis in a dog’s ear, including the signs, causes, and how to prevent it.
What is chronic canine otitis?
Chronic otitis (ear infection) is a condition that affects a dog's ear canal. It can be external (involving the outer ear canal only), media (affecting the middle ear), or interna (involving the inner ear and associated structures). Ear infections primarily affect the external ear canal and, to a lesser extent, the middle and inner ear.
Causes & Pathogenesis of Chronic Otitis in Dogs
An ear infection is usually caused by irritation of the skin lining the ear canal. This irritation leads to inflammation and an overgrowth of yeast and bacteria, which in turn causes itching and further inflammation. Scratching can result in injuries to the ear.
Any dog, regardless of ear shape, water exposure, or the amount of hair inside the ear canal, can develop an ear infection. In most cases, the underlying cause of the irritation is allergic or unrelated to the shape of the ear and moisture. Environmental allergies and food allergies can also cause an allergic skin reaction leading to otitis externa.
Other less common causes of otitis externa in dogs include:
- Polyps or other growths in the ear canal
- Foreign bodies in the ears, including dirt, sand, or plant material (foxtails and grass awns)
- External parasites (like ear mites)
Chronic otitis is a painful condition resulting from inflammation, infection, and thickening of the tissues in the ear canal. This leads to the narrowing of the canal, ruptured eardrums, and accumulation of debris and infection in the middle ear. Over time, scar tissue blocks the canals, making it difficult for medications to reach the affected areas and preventing the natural shedding of skin cells, sebum (wax), and hair from the canal.
How a Dog's Ears Become Infected
Exposure: Exposure to irritants, parasites, or illness can lead to irritation in the ear.
Adhesion: Damage caused by irritation in the ear tissue creates an opening for bacteria and yeast.
Invasion: The bacteria or yeast enter the body and begin to multiply.
Infection: An ear infection (otitis) develops.
Transmission: While otitis itself cannot be transmitted to other animals, illnesses or parasites related to otitis can be.
Another great example of why preventive care is so important is that dogs can spread colds and other illnesses even when they are not displaying obvious symptoms. This can potentially lead to ear infections.
Signs of Chronic Otitis in Dogs
Chronic otitis is a frustrating disease for both owners and veterinarians. Still, it is far more uncomfortable for patients due to the pain and nagging itchiness that these ear infections cause.
The clinical signs of otitis you may notice in your dog will depend on the severity of the inflammation, but may include:
- Shaking the head or rubbing the head and ears on the floor or furniture
- Scratching at the ears
- Discharge from the ears, which can sometimes have a foul odor
- Redness of the ear canal and earflap (the ears may also feel warm when touched)
- Ear hematoma, evidenced by a grossly swollen earflap
- Aggression whenever you try to touch the head or ears
The infection can progress into the middle and inner ear, leading to more severe symptoms such as head tilt, incoordination, inability to stand or walk, hearing loss, and intense, unrelenting pain. Severe or chronic otitis can cause the outer ear canal to thicken and deformed, making ear cleaning difficult.
Chronic otitis is usually diagnosed based on a history of previous ear infections and signs observed during a physical examination. Redness, inflammation, discharge, and other changes within the ear can indicate the presence of an ear infection. However, determining the types of microorganisms causing the inflammation can be challenging. Specialized diagnostic testing, such as otic cytology, will likely be recommended.
Treatment Options for Otitis in Dogs
Your vet's recommendations for treating otitis in dogs will depend on the cause of the infection. Your vet will address the components, bacterial or fungal, and the inflammation with antibiotics.
Treatment for dogs experiencing otitis often includes:
- A thorough cleaning of the ear canal to remove accumulated debris. If the otitis is painful and/or lengthy, cleaning should ideally be done while the pet is sedated or anesthetized. Otoscopy is frequently used as a tool in this process.
- Treatment of bacterial infections, yeast infections, or mites using topical medication such as ear drops or ointment. Your vet may prescribe medications like antibiotics, antifungals (to kill yeast), anti-inflammatory drugs (such as cortisone), and topical anesthetics.
- In some cases, such as when the eardrum is ruptured, systemic antimicrobials (antibiotics administered by mouth or injection) are indicated. Antibiotic therapy should ideally be based on culture and sensitivity testing results.
- Systemic anti-inflammatory medications, such as corticosteroids, sometimes alleviate pain, redness, and swelling. Antihistamines may also be prescribed.
To stop this disease, the underlying illness must be treated. Treatment options may range from mass removal and mite killers to diet changes and allergy injections. If your dog's ear infection is severe, or if your pup suffers from chronic otitis, surgical intervention may be required. If your dog requires further diagnostic testing or treatment not available at Harbor Animal Hospital, you may be referred to a veterinary surgical specialist near Torrance.
How to prevent chronic canine otitis?
Ear infections are typically better prevented than treated. Keeping your dog's ears clean and dry can help reduce ear infections. Talk to your primary vet about the best cleaning solution for your pup, and take the time to give your dog a weekly ear cleaning. Drying your dog's ears is also good if they have spent time in the water.
Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.
