Feline eosinophilic keratitis

Eosinophilic keratitis, or proliferative keratoconjunctivitis, is a chronic keratopathy that affects cats and horses. It is caused by a suspected immune mediated response to an unknown antigenic stimulus. A 5-year-old, spayed female, Domestic Short-haired cat was referred to the Ophthalmology Section of the Hospital de Clinicas Veterinarias at Federal University of Rio Grande do Sul. It had a history of ocular discomfort and ulcerative keratitis, with white plaque affecting a variable portion of the cornea and bulbar conjunctiva, in the left eye, that was nonresponsive to treatment for several months. The right eye was normal. A diagnosis of eosinophilic keratitis was made based on clinical signs and cytologic examination of corneal scrapings. The presence of eosinophils, eosinophilic granules, and mast cells on corneal scrapings is considered diagnostic for eosinophilic keratitis. The cat responded to topical corticosteroids and thirty days after treatment the plaques had completely resolved. Based on the literature available, this is the first case of eosinophilic keratitis in a cat reported in Brazil.