Ear infection in cats

Ear infections in cats (otitis externa) can cause significant itching, irritation and pain. If symptoms occur in one or both ears, the cat should be examined by a veterinarian so that the cause can be identified and appropriate treatment can be initiated.

Symptoms of ear infection in cats

• Shaking of the head.
• The cat scratches itself with its paw or rubs its head against things.
• Visible earwax or secretions.
• Redness, swelling and scabs.
• Sour or unpleasant odor.
• Pain when touched.
• Reduced hearing and balance problems.

A cat's ear is anatomically different from a dog's.

The cat's ear consists of the outer ear, the middle ear, and the inner ear. In cats, the tympanic cavity is divided into a dorsolateral and a larger ventromedial compartment by a bony septum, with a small opening connecting the two. The dorsolateral compartment can be accessed via the ear canal and tympanic membrane, while access to the ventromedial compartment may be more difficult and in some disease states may require surgical access. If middle ear disease is suspected, imaging such as CT may be appropriate to map the extent. This anatomy is an important difference between cats and dogs and can affect both diagnosis and treatment.

The general mechanisms behind ear infections — how predisposing, primary, secondary, and maintaining factors interact — are largely the same in cats as in dogs. Read more about this in our article about ear infections in dogs. Here we focus on what is special for cats.

Why do cats get ear infections?

Ear mites (Otodectes cynotis) is the most common primary cause of ear infections in cats. The mite is transmitted through close contact between animals and is therefore more common in kittens, cats in multi-cat households, and cats that have a lot of contact with other cats — not just because the cat spends time outdoors.

Other possible causes and contributing factors:

• Allergy.
• Foreign bodies in the ear.
• Narrow ear canals.
• Inflammatory polyps or tumors.

Inflammatory polyps

Inflammatory polyps are benign growths that occur particularly in younger cats. The cause is not fully understood. The polyps may originate in the middle ear or eustachian tube and cause symptoms in the ear, pharynx, or both. If a polyp extends into the ear canal, it can often be visualized with a video otoscope and, in selected cases, removed via the ear canal. Other cases require further imaging or surgical treatment to gain access to the polyp's origin.

Diagnosis and treatment of ear infection in cats at A-Vet

First visit: examination and cytology

We start with a clinical examination of the cat and the ear, and assess the ear canal with an otoscope as far as possible. We usually take samples from the ear for microscopic examination. The samples can be examined for ear mites, among other things, and by cytology we assess yeast, bacteria and inflammatory cells. This provides important information about what is going on in the ear and forms the basis for further treatment.

Next visit: ear irrigation with video otoscope if needed

If the ear canal contains a lot of secretion or material, the eardrum is difficult to assess, or we suspect a polyp, we may recommend thorough ear irrigation with a video otoscope.

The cat's ear canal is narrow and sensitive, and at our clinic this procedure is performed under general anesthesia with continuous monitoring. The anesthesia keeps the cat completely still, while the veterinarian examines and treats the ear in a controlled and gentle manner.

We use a Karl Storz video otoscope, which provides a magnified image of the ear canal and eardrum on a screen. Via the instrument's working channel, we can rinse the ear canal with temperate physiological saline (0,9%), aspirate the rinsing fluid and secretions and, if necessary, remove wax or other material under direct visual control. If we find a polyp extending into the ear canal, the veterinarian will assess whether it can be removed via the ear canal or whether further imaging or surgical treatment is necessary.

Further visits: check until the ear is under control

After treatment, we schedule follow-ups based on the extent of the ear infection and how the cat is responding. If necessary, new samples are taken for cytology, so that we can compare with previous findings. The fact that the cat is itching less or that the ear looks better does not necessarily mean that the treatment is complete — we use both the clinical examination and cytology when assessing whether the result is satisfactory, and continue to follow up until we are satisfied with the development.

Otitis media in cats

Otitis media can occur together with disease of the external ear canal, but in cats the middle ear can also be affected without obvious signs of external otitis. In the case of chronic or recurrent ear problems, neurological symptoms or suspicion of disease behind the eardrum, the veterinarian therefore considers whether the middle ear may be involved. Video otoscopy, sampling from the middle ear and imaging such as CT may be appropriate depending on the findings.

How to prevent ear problems in cats

• Do not clean healthy ears unnecessarily. A healthy cat ear does not need regular cleaning, and excessive cleaning can disrupt the ear's natural self-cleaning mechanism.
• Avoid sharp objects in the ear. This can damage the ear canal or eardrum.
• Get to know your cat's normal ears. This makes it easier to detect changes in odor, discharge, redness, or sensitivity early.
• Get recurring ear problems investigated. Recurrent episodes may be due to an underlying cause, such as a polyp, which must be addressed for lasting control.

Also read about ear infections in dogs.