Uveitis is an inflammation of the inner pigmented structures of the eye. It is one of the most common inner eye conditions of cats, in part because a number of feline infectious diseases can involve the eye. They include feline leukemia (FeLV), feline infectious peritonitis (FIP, especially the granulomatous form), feline immunodeficiency virus (FIV), toxoplasmosis, herpesvirus, bartonella, systemic fungal infections, and the larvae of roundworms and heartworms. Uveitis may also be caused by penetrating eye injuries, blood-borne bacterial infections, and eye tumors. Uveitis is a serious disorder that can lead to blindness.
Uveitis is painful. The cat squints, and the affected eye waters. Other distinguishing signs of uveitis are surface redness and a small pupil. When you push with your finger against the eyelid, the eye is tender and feels like a soft grape. Some cats will show a clouding or edema of the cornea and there may be new blood vessels growing across the cornea. Blood or pus may leak into the front area of the eye. The accumulation of inflammatory cells may cause the iris to stick to the lens and lead to secondary glaucoma as a result of scar-type damage.
Cats with acute uveitis will have low intraocular pressure. This can especially be seen when the pressures of both eyes are compared. Serology tests and titers may be done to look for the inciting cause.
Treatment: Any underlying infectious or systemic illness should be treated. Corticosteroids reduce intraocular inflammation, but they are used with caution to prevent exacerbating an underlying systemic illness. Eyedrops such as atropine may be used to dilate the pupil and relieve pain. Treatment must be administered under veterinary supervision. Antibiotics may be given as well to help battle infections. Clindamycin is often used, as well as azithromycin, to treat toxoplasmosis or bartonella.
Chronic uveitis that goes untreated may be associated with the development of intraocular cancer.
This article is excerpted from “ Cat Owner’s Home Veterinary Handbook” with permission from Wiley Publishing, Inc.