What is Uveitis in Cats?

Introduction

When Sarah noticed her normally curious and agile cat, Whiskers, was acting lethargic and seemed to avoid bright lights, she knew something wasn’t right. She was alarmed to see redness and cloudiness in Whiskers’ eyes, prompting an urgent visit to the veterinarian. It was there that Sarah learned her beloved cat was suffering from uveitis. This blog post will explore the complex world of uveitis in cats, providing insights into the causes, symptoms, and treatments for this potentially severe eye condition.

Uveitis is a painful and potentially blinding condition that affects cats. It occurs when the uvea, the middle layer of tissue in the eye’s wall, and the ciliary body become inflamed due to an immune response from the body or an attack by a virus. This inflammation can cause swelling, redness, and pain around the eyes.

There are many types of Uveitis, including anterior Uveitis, Posterior Uveitis, and intermediate Uveitis.

• Anterior Uveitis (anterior synechiae) occurs when the iris adheres to the lens capsule. This causes blurred vision and may lead to cataracts.

Cats with Uveitis may often have cloudy eyes because the iris sticks to the back surface of the lens. The most common cause of anterior Uveitis in cats is feline herpesvirus infection. However, this condition can also be associated with other viruses, including feline calicivirus, feline immunodeficiency virus, toxoplasmosis, and chlamydophila felis.

• Posterior uveal melanoma (PUM) is rare cancer affecting only cats. Uveitis is inflammation of the iris and choroid of the eye. Posterior uveal melanomas usually occur in older cats, and most cases are fatal.
• Cats with intermediate Uveitis often experience blurred vision, floaters (floating particles), flashes of light, and pain in the eyes. These symptoms may be mild or severe, depending on the severity of the disease.

What is the Uvea?

The uvea (pronounced oo-VEE-uh) is a thin layer of tissue between the iris and cornea of the eye. The uvea contains blood vessels and nerves that help regulate the body’s temperature. Uveitis occurs when this delicate area becomes inflamed.

The uvea is divided into three layers: the anterior chamber, the posterior chamber, and the vitreous humor.

When cats develop Uveitis, the result is usually painless redness and swelling of the eyes. This condition may be temporary or permanent.

What are the Causes of Uveitis in Cats?

Uveitis occurs when there are particles of foreign material in the eye. These particles can come from outside sources like dust, pollen, molds, plants, insects, bacteria, viruses, fungi, and parasites. They can also originate inside the body, like in cases where the cat swallows something that gets stuck in the esophagus. In some cases, the source of the problem needs to be identified. This type of Uveitis is called idiopathic. Uveitis from a nonocular source (40% to 60%) is usually diagnosed as idiopathic.

Other factors that increase the risk of Uveitis include certain types of diabetes mellitus, autoimmune diseases, and infections.

Another cause of Uveitis is an immune-mediated disease. The second leading cause of Uveitis is infectious diseases such as toxoplasmosis, herpes simplex virus(HSV), cytomegalovirus(CMV), and varicella zoster virus(VZV). Other less common causes include trauma, chemical exposure, metabolic disorders, autoimmune diseases, and genetic factors.

Immune-mediated Disease

Uveitis commonly happens because the body’s immune system mistakenly attacks its tissues. This type of autoimmune disease is known as Immune-Mediated Disease. The most common form of Uveitis in cats is the Feline Leukemia Virus (FeLV), which affects the immune system.

Feline Infectious Peritonitis

If Uveitis occurs in cats, it usually happens after the cat has been exposed to an infectious agent. The most common cause of feline Uveitis is the FIP virus. This viral infection spreads through direct contact between infected animals and contaminated environments.

Trauma

Traumatic injury causes damage to the blood vessels in the eye. This leads to bleeding and swelling of the tissue surrounding the affected eye. The result is pain, redness, and blurred vision.

Chemical Exposure

Chemical exposure can cause Uveitis through direct contact with chemicals, inhalation of fumes, or ingesting contaminated food or water. The most common form of chemical-induced Uveitis is called iritis. This occurs when chemicals enter the body through the eyes and irritate the iris and ciliary body.

Metabolic Disorder

Metabolic disorders include diabetes mellitus, hyperthyroidism, hypothyroidism, Addison’s disease, Cushing’s syndrome, and others. These diseases cause abnormal production of hormones, resulting in elevated blood glucose levels. High blood glucose levels damage the retina, causing vision loss.

Symptoms of Cats with Uveitis

Symptoms vary depending on the type of Uveitis. They may include blurred vision, floaters, flashes of light, sensitivity to bright lights, decreased night vision, and double vision. In some cases, there may be no symptoms at all.

There may be a clear liquid flowing from the eye, redness and swelling around the eyes, discharges from the eyes, cloudy or watery vision, pain, and sometimes even blindness.

Diagnosing Uveitis in Felines

A thorough history and physical examination are critical to diagnosing cats. Your veterinarian will perform a complete ophthalmic exam to look for signs of infection, trauma, tumors, retinal detachment, glaucoma, or other diseases. They will also examine the eyes for evidence of trauma, such as corneal abrasion, ulcers, or punctate lesions.

Bloodwork and imaging studies should also determine the condition’s underlying cause. If you suspect your cat has Uveitis, it is essential to seek veterinary care immediately. In addition, you can consult the following resources for information about how to diagnose and treat feline Uveitis.

Treatment for Uveitis in Cats

The treatment of Uveitis depends on what type of Uveitis you have.

There are two main categories of treatment for Uveitis: medical therapy and surgical removal of inflamed tissues. Medical therapy includes corticosteroids, immunomodulators, antibiotics, and antifungals.

1. Topical steroids are used to treat mild forms of Uveitis. Topical steroids work by decreasing the immune response and reducing swelling. They’re usually applied directly to the affected area. Corticosteroid drops are available over the counter at drugstores.
2. Immunomodulators are drugs that suppress the immune system. These include azathioprine, cyclosporine, methotrexate, and tacrolimus. Immunomodulators are often prescribed after the patient fails to respond to steroid therapy.
3. Antibiotics are used to treat bacterial infections. Antibiotic ointments are applied topically to infected areas.
4. Antifungal agents are used to treating fungal infections. Antifungal creams and lotions are applied to infected areas.
5. Surgery is performed only when necessary. Surgery removes inflamed tissues and replaces them with healthy tissues. Surgical procedures include laser photocoagulation, cryotherapy, vitrectomy, and pars plana vitrectomy.

Prevention of Feline Uveitis

The best way to prevent uveitis in cats is by regularly taking them for check-ups at their vet clinic. Early detection and initiation of treatment are crucial to avoid further health issues.

1. Other preventative steps include keeping your cat indoors, away from other potentially infected animals or irritants that could damage their eyes
2. Provide adequate nutrition with taurine supplementation
3. Regular cleaning of litter boxes
4. Vaccinating against diseases that may lead to uveitis
5. Avoid contact with chemicals or gases that could enter the eye.

Cat owners should also be aware of common signs and symptoms of uveitis so they can get professional help immediately. These include redness/swelling/inflammation around the eye, reduced vision or a “glazed” appearance to the cornea, discharge from the eye, sensitivity to light, squinting/closing one eyelid more than usual, and occasional blinking or jerking movements of a limb as if being irritated by something invisible.

If owners notice these signs or symptoms in their cats, they must be brought up immediately with their veterinarian for further examination and diagnosis. A proper diagnosis will help identify what type of uveitis is occurring so it can be treated effectively before causing lasting harm. The vet may prescribe topical ointments/ointments, oral medications like NSAIDs (nonsteroidal anti-inflammatory drugs) or systemic steroids such as prednisone, depending on the type of uveitis detected.

Frequently Asked Questions