What is Otitis in Dogs and Cats?

Otitis is an all encompassing term for  ear disease in cats and dogs, which can be  caused by parasites, foreign bodies (like grass seeds) and allergic skin disease,  which results in Inflammation of both the skin of the ear flap and also the skin lining the ear canals. There are three types of Otitis in dogs and cats; Otitis Externa, Otitis Media, and Otitis Interna.

Otitis Externa affects the ear canal right down to the eardrum. Inflammation to the middle ear cavity at the base of the skull is called Otitis Media. Otitis Interna refers to inflammation within the hearing centre of the brain. 

Which Breeds are Predisposed to Otitis?

Unfortunately, some breeds tend to have a predisposition to Otitis. This does not mean that such breeds are guaranteed to develop Otitis throughout their lifetime, but they are at a higher risk of developing the disease. These breeds include:

Basset Hound

Golden Retriever

Labradoodle

Cockapoo

Chinese Shar Pei

Beagle

On the other hand, breeds with the lowest prevalence to Otitis include:

Jack Russel Terrier

Yorkshire Terrier

Border Collie

Chihuahua

What Causes Otitis in Dogs and Cats?

Otitis can be caused by a number of factors and other conditions which cause inflammation of the skin. Below you’ll find specific information about primary, predisposing, and perpetuating factors which may cause or be an attributing factor to ear disease.

Primary Factors:

The ear canal is lined with skin, and many skin diseases and other skin conditions can act as primary causes of inflammation. These diseases alter the environment of the ear canal, causing inflammation and, sometimes, infection as a secondary condition

Examples of primary factors include:

• Allergies – Food, Atopic Dermatitis, Environmental
• Parasites
• Autoimmune/immune-mediated
• Endocrine diseases, such as Hypothyroidism and Hyperadrenocorticism
• Epithelialization disorders  (seborrhoea)
• Foreign bodies
• Glandular disorders
• Fungal 
• Viral (distemper).

Predisposing Factors:

Whilst there are a number of breeds which are predisposed to Otitis, there are also a variety of predisposing factors that can alter the microclimate of the ear canal, placing cats and dogs at risk of developing Otitis. These include:

• Conformation (pendulous pinna, stenotic canals, hairy concave pinna, excessive hair in canals)
• Excessive moisture in their environment, e.g. from regular swimming
• Obstructive ear disease 
• Primary otitis media (Often seen in Cavalier King Charles Spaniels)
• Systemic diseases, such as Immune suppression and Catabolic states
• Treatment effects (changes in normal flora, trauma)

Perpetuating Factors:

Perpetuating factors that may cause Otitis arise as the result of the changing environment within the ear canal and secondary pathological changes, i.e. the more ear infections a dog has the more likely a dog is to have recurring ear infections. Such perpetuating factors can include:

• Epithelial changes  (thickening of the skin after ongoing Otitis)
• Changes within the ear canal, such as Stenosis, Edema, and proliferative changes like scarring 
• Ruptures of the eardrum
• Glandular factors
• Pericartilaginous Fibrosis or calcification
• Middle ear disease

Symptoms of Otitis in Dogs and Cats

Unfortunately, you can’t visibly see inflammation in the ear canals of cats and dogs, however, there are a number of signs and symptoms to look out for which usually indicate that something isn’t right. These may include:

• Shaking of the head
• Signs of pain
• Unusual, unpleasant odours
• Redness of the ear flap or entrance to the canal
• Ulceration or discharge at the entrance to the canal
• Swelling

How is Otitis Diagnosed?

To diagnose Otitis, veterinary dermatologists will usually conduct a thorough history alongside a clinical examination using otoscopy which allows them to see into the ear and assess the condition of the ear. This may need to take place under anaesthesia to allow use of video otoscopy for a more detailed assessment.

The ear canal is checked for stenosis, erythema, erosion/ulceration, glandular hyperplasia, exudate, and masses, whilst the tympanic membrane is examined for bulging, rupture, or changes in colour. Sometimes cleaning or flushing may be required to be able to see the tympanic membrane.

Your vet will  also take samples  which can then be used for cytology. Cytology is the microscopic examination of cells, which helps vets to understand what is causing your pet’s inflammation. It is usually minimally invasive, but can go a long way in making accurate diagnoses, and for informing treatment. 

How is Otitis Treated?

Once the veterinary dermatologist has confirmed the diagnosis, they will then be able to recommend a suitable treatment plan. However, they must first have an understanding of what is causing the condition as one of the key treatment methods is to manage underlying causes. Another key method (both may be used in conjunction) is to prescribe antimicrobials or anti-inflammatories, but this will depend on the underlying cause of the condition.

To help matters along, pets will also be treated for the symptoms of Otitis, such as pain and itching, and the vet will often demonstrate how to effectively and safely clean pets’ ears, as this will be essential in managing the condition.

Small Animal Dermatology Services at Knutsford Vets Surgery

Knutsford Vets offer a range of veterinary dermatology services to help diagnose and treat your pet’s skin conditions. If you notice any of the symptoms and signs of Otitis, get in touch with us as soon as possible and we’ll work with you to get to the root of the problem, before recommending a suitable care plan and tailored advice.