Feline Conjunctivitis and Keratitis

The most common clinical signs include red and swollen conjunctiva with excessive tearing, ocular discharge, and/or squinting. The discharge ranges from clear mucous to green-yellow in color. Sneezing and nasal discharge may also accompany the ocular signs, especially in younger cats.

Recurrent bouts are common, especially in viral cases such as feline herpes virus. Severe infections can cause complications such as permanent scarring. In young kittens, the inflammatory response may cause adherence of the conjunctiva to the cornea. The most severe cases can lead to rupture of the globe and vision loss. When severe infections occur, corneal ulceration may lead to perforation of the eye. With long-standing ulcers, a corneal sequestrum can form.

Several diagnostic tests may be required to confirm the cause, including microscopic evaluation, virus isolation, and PCR testing. Superficial corneal ulcers can usually be treated with medications; however, large or deep corneal ulcers and corneal sequestrum may require surgical intervention such as keratectomy and conjunctival grafting. With chronically infected eyes containing excessive scarring, scar tissue may be surgically reduced to improve vision or tear drainage.