Uveitis in Cats

Uveitis is a painful eye inflammation affecting a cat's uvea that can potentially occur as a result of another underlying cause and it should not be ignored. It can progress to permanent blindness if left untreated. Knowing how to recognize the sometimes subtle signs can help keep your cat comfortable and fully sighted.

What Is Uveitis?

Uveitis occurs when the uvea, a part of a cat's eye, becomes inflamed. The uvea actually consists of three parts of the eye: the iris, the choroid, and the ciliary body. The different parts of the uvea play various roles within the eye and are important for maintaining eye pressure, vision, the shape of the eye, and more. Any or all of these parts of the uvea may become inflamed with uveitis. Here's what each part of the uvea is responsible for in your cat:

• Iris: The iris is the part of the eye that gives your cat its eye color,
• Ciliary body: This part lines the wall of the eyeball and produces the fluid inside it.
• Choroid: The choroid is the middle layer of the eye.

Depending on what part or parts of the uvea become inflamed, uveitis can be classified in three different ways and may occur in one or both eyes.

• Anterior uveitis: Only the ciliary body and iris are inflamed.
• Posterior uveitis: Only the choroid is inflamed.
• Panuveitis/true uveitis: The ciliary body, iris, and choroid are all inflamed.

Symptoms of Uveitis in Cats

Some of the symptoms of uveitis can be very subtle since the damage may be occurring deep in the eye and only a veterinarian can spot it with specific tools used to diagnose the condition. However, if you see a change in your pet's behavior based on some of the following signs, call your vet for an exam.

Pawing at Eyes

Cats with uveitis are usually in a lot of pain and will be pawing at the affected eye.

Keeping Eyes Shut

A cat with this disease will commonly hold the painful eye or eyes shut.

Avoiding Being Pet on the Head

Your cat may show aggression or reluctance when you attempt to pet it on its head, which is usually a response to avoid further pain.

Squinting

Your cat may stay in a state of static or repeated squinting in an attempt to relieve the pain or to try to see better.

Repeated Blinking

A cat with this condition may blink repeatedly as a way to try to relieve the pain.

Avoiding Bright Light

Avoidance of bright lights is not uncommon when a cat has this disease.

Eye Redness

The blood vessels in the eyes of a cat with uveitis may be more pronounced than usual due to the swelling and inflammation in the area.

Eye Discharge

Additionally, sometimes clear, white, or purulent discharge may be seen in the corner of the eye in a cat with uveitis.

Cloudiness of the Eye

If you are able to get a look at your cat's eye, there may be inflammation in or around the eye and it may appear cloudy or even tinged with blood.

Protruding Third Eyelid

A cat's third eyelid may become involuntarily visible. This could occur for a number of reasons but may be because the eye is inflamed, there's extreme intraocular pressure, or an infection is affecting the nerves that make the third eyelid functional.

Bumping Into Things

If left untreated, blindness can occur and your cat may start bumping into things in your home.

Causes of Uveitis

There are numerous reasons why a cat may develop uveitis in one or both eyes or in different parts of the eye. Common causes of uveitis in one eye could be the result of trauma to the area, parasites, or cancer. If uveitis affects both eyes, it may be due to a viral or bacterial infection (such as FIP or feline leukemia), immune-mediated disease (such as FIV), or a metabolic disease (such as diabetes) that's causing an extreme inflammatory response in your cat.

Diagnosing Uveitis in Cats

If you suspect your cat has uveitis or another eye issue, your veterinarian will need to perform a full physical examination. A thorough eye examination may include using the following methods to assess your cat's eye pressure, function, and if there is an underlying disease that is causing the uveitis:

• Special lights
• Magnifying glasses
• Eye drops
• Blood test
• Urine test
• X-ray
• Ultrasound
• Cytology (examination of eye fluid)
• Retinal biopsy (in extreme cases)

Your regular veterinarian may even refer your cat to a veterinary ophthalmologist for further examination and diagnostic testing depending on the cause and severity of the uveitis.

Treatment

The treatment of uveitis will vary depending on the underlying reason for it but regardless of the cause, the inflammation and pain in the eye should be addressed. Eye drops and various oral medications may be used to help relieve the discomfort your cat is experiencing, decrease the inflammation in the eye, and treat or prevent infection. The condition can clear up within 24 hours to a few days of treatment. If therapy to relieve the pain in your cat's eyes fails, removal of the affected eye or eyes may be necessary.

Prognosis for Cats With Uveitis

A cat treated in a timely manner for uveitis will have an excellent outcome. If the uveitis is recurrent or complicated, your vet may refer you to a veterinarian ophthalmologist. A cat untreated for uveitis may develop glaucoma, cataracts, retinal detachment, or retinal degeneration which can lead to blindness.

How to Prevent Uveitis

While some causes of uveitis are difficult, if not impossible, to prevent, there are steps you can take to decrease the likelihood of it occurring in your cat:

• Treat any eye infections in your cat promptly.
• Keep a tight control on your cat's health, especially if it has diabetes and high blood pressure.
• Avoid damaging your cat's eyes or exposing them to potential toxins.
• Maintain regular veterinary check-ups which can help detect small problems before they become big issues.