Chronic otitis is a long-term ear infection that can affect any dog and cause itchy, painful, and smelly ears. Today, our Jackson vets will discuss chronic otitis in a dog's ear, the signs, and how it is treated.
An Overview of Chronic Otitis in Dogs
Chronic otitis is a common disease of the dog's ear canal, which may be external (of the external ear canal only), middle (involving the middle ear) or internal (involving the inner ear and associated structures). It mainly affects the external auditory canal and, to a lesser extent, the middle and inner ear, making it a dermatological condition.
An ear infection is generally caused by irritation of the skin lining the ear canal, leading to inflammation and the proliferation of yeast and bacteria. This causes itching and inflammation, leading to self-trauma.
Any dog, regardless of the shape of its ear, its exposure to water, or the amount of hair inside the ear canal, can develop an ear infection. In most cases, the underlying cause of irritation is allergic or unrelated to conformation and humidity. Environmental and food allergies can also provoke an allergic skin reaction leading to otitis externally.
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 caused by inflammation, infection and thickening of the ear canal tissues. This leads to the narrowing of the ear canal, rupture of the eardrum and the presence of debris and infection in the middle ear. Over time, scar tissue obstructs the canals, preventing the medication from reaching the diseased parts of the canal and preventing the natural removal of skin cells, sebum (wax) and hair from the canal.
Chronic otitis is a frustrating condition for owners and vets alike, but it's far more critical for patients because of the persistent pain and itching these ear infections cause.
Signs of Chronic Otitis in Dogs
The clinical signs of otitis 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 the head is approached
The progression of this infection into the middle and inner ear can lead to even more severe clinical symptoms, such as head tilt, incoordination, inability to stand or walk, hearing loss and intense, unrelenting pain. If otitis is severe or chronic, the external auditory canal may thicken and deform, making it difficult to clean the ears.
To diagnose an ear infection, the veterinarian may rely on medical history and physical examination findings. The medical history may include attempts to determine the duration of the ear infection, whether it has occurred before, and whether other signs of illness have been observed. The results of the physical examination may reveal signs of an underlying disease, such as thyroid disease or Cushing's disease.
Chronic otitis is usually diagnosed based on a history of ear infections and the results of physical examination. Redness, inflammation, discharge and other changes in the ear easily indicate the presence of an ear infection, but the more difficult part is determining what types of microorganisms are exploiting the dog's inflamed ears and what the root cause of the inflammation is. In this case, specialized diagnostic tests, such as otic cytology, will probably be recommended.
Treatment for Chronic Otitis in Dogs
Chronic otitis treatment entails addressing the bacterial and fungal components, as well as the inflammation, with antibiotics.
The treatment steps are usually as follows:
- Cleaning the ear canal is always advised to remove accumulated debris. If the otitis is painful and/or a lengthy process, cleaning should ideally be done while the pet is sedated or anesthetized. Otoscopy is frequently recommended as a tool in this process.
- Typically, topical medication tailored to treat the specific bacteria, yeast, or mites present is used (these are usually available as ear drops or ointments). Antibiotics, antifungals (to kill yeast), anti-inflammatory drugs (such as cortisone), and topical anesthetics are examples of these.
- 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 the results of culture and sensitivity testing.
- To alleviate pain, redness, and swelling, systemic anti-inflammatory medications such as corticosteroids are sometimes used. Antihistamines may be prescribed as well.
To stop this disease, the underlying illness must be treated, which can range from mass removal and mite killers to diet changes and allergy injections. In difficult cases, surgical intervention may be required.