Feline eosinophilic keratoconjunctivitis: a retrospective study of 45 cases (56 eyes)

Abstract

The medical records of 45 cases (56 eyes) of feline eosinophilic keratoconjunctivitis (EKC) diagnosed between 2005 and 2011 were reviewed. Cats were included if a clinical diagnosis of EKC was recorded and eosinophils were found on corneal cytology. Median age at presentation was 5 years (interquartiles 5-9 years) for both males and females. Domestic shorthair was the predominant breed, accounting for 77.8% of the cats. The condition was unilateral in 75.6% of cases, with the superotemporal quadrant of the cornea the most frequently affected position (76.8% of eyes). A history of corneal ulceration was recorded in 37.8% of cases, and corneal ulcers were present at or before diagnosis in 66.7% of the cats. Eosinophils were found in 92.0% of conjunctival scrapings. We performed polymerase chain reaction (PCR) for feline herpesvirus type 1 (FHV-1) for 33/45 cats. Viral DNA was detected in 54.5% of these cats. FHV-1 DNA was detected by PCR in 66.7% of cats with a history and/or presence of a corneal ulcer at first presentation, which is significantly more than those with no corneal ulcer at any time (22.2% FHV-1 DNA detected). Our findings suggest that a corneal ulcer can be present prior to the development of eosinophilic keratitis. Further studies are mandatory to explore the role that FHV-1 could play in EKC-associated corneal ulceration.

Equine eosinophilic keratoconjunctivitis in California: retrospective study of 47 eyes from 29 cases (1993‐2017)

“…A type IV hypersensitivity response (ie, a delayed hypersensitivity response) is suspected and may be associated with an environmental or parasitic allergen . Eosinophilic keratoconjunctivitis has been reported in several domestic species, including horses, donkeys, cats, and rabbits . An apparently similar disease process, vernal keratoconjunctivitis (VKC), affects people and is defined as a chronic, bilateral, allergic conjunctivitis in patients that often have a history of atopic disease.…”

Feline Epitheliotropic Mastocytic Conjunctivitis in 15 Cats

“…Moreover, feline epitheliotropic mastocytic conjunctivitis is characterized by the presence of mast cells within the conjunctival epithelium, a feature that has not been described previously in association with eosinophilic keratoconjunctivitis or eosinophilic conjunctivitis. 1,3 Nonetheless, mast cells have been described within the corneal epithelium of cats with feline eosinophilic keratitis. 21 Cytologic evaluation from these patients does not seem to be sufficient for the diagnosis of feline epitheliotropic mastocytic conjunctivitis, as similar findings are seen in feline eosinophilic conjunctivitis or keratitis, conjunctival mast cell tumors, or other causes of feline conjunctivitis (eg, C. felis, M. haemofelis).…”

“…21 Cytologic evaluation from these patients does not seem to be sufficient for the diagnosis of feline epitheliotropic mastocytic conjunctivitis, as similar findings are seen in feline eosinophilic conjunctivitis or keratitis, conjunctival mast cell tumors, or other causes of feline conjunctivitis (eg, C. felis, M. haemofelis). 1,3,9 Due to cytologic similarities between feline eosinophilic conjunctivitis and feline epitheliotropic mastocytic conjunctivitis, the authors considered the possibility that feline epitheliotropic mastocytic conjunctivitis may be an uncommonly severe variant of feline eosinophilic conjunctivitis. In humans, vernal conjunctivitis varies in severity and may range from mild hyperemia and chemosis, to cobblestone-like papillae, or to large papillary conjunctival lesions in severe cases.…”

“…Tissue infiltration by mast cells occurs in cats with mast cell tumors, 2,13,15 eosinophilic keratitis, 3 eosinophilic conjunctivitis, 1,19 and papular mastocytic dermatitis. 17 Papillary conjunctivitis with intraepithelial mast cells has been described in people with vernal 11 or giant papillary 10 conjunctivitis but not with allergic or atopic conjunctivitis.…”

Pathology in Practice

“…[2][3][4][5][6][7][8] Immunosuppression is thought to have a role in the development of FHV-1-associated clinical disease. [2][3][4][5][6][7][8] Immunosuppression is thought to have a role in the development of FHV-1-associated clinical disease.…”