Page 1269 - Problem-Based Feline Medicine

61 – THE CAT WITH A CLOUDY EYE 1261

light coffee-colored stain to an intense thick black
EOSINOPHILIC KERATITIS*
plaque.
Approximately 80% are associated with herpetic Classical signs
keratitis. There may be a history of previous infec-
● Irregular white to pinkish plaque on the
tion with FHV-1 as a kitten, or later in life, with
cornea.
herpetic keratitis. However, cases may develop after
● Corneal edema and vascularization.
corneal ulceration or from medial entropion.
● +/- Similar conjunctival lesion.
The disease is initially seen unilaterally, but eventually ● Unilateral or bilateral.
both eyes may become involved. ● Poor response to a variety of antibacterial
agents.
Initially the cat may not show any signs of discomfort,
but as the lesion progresses blepharospasm and pho-
See the main reference on page 1245 (The Cat With
tophobia develop.
Abnormalities Confined to the Cornea).
Early, light-staining lesions have an intact epithelium
and do not stain with fluorescein. Lesions that have
Clinical signs
developed a dense plaque may have a fine ring of
ulceration surrounding the lesion, which may stain Signs begin unilaterally, but may become bilateral.
positive with fluorescein.
Seen as a cloudy, red cornea. This is a proliferative
In mild cases, the surrounding cornea will not show lesion producing whitish to pink, plaque-like tissue
signs of edema or vascularization, but as the degree of that may be covered by a thick white discharge.
degeneration progresses, corneal edema with
The corneal epithelium is usually intact, but may show
marked deep stromal vascularization may be
patchy staining with fluorescein. There is usually an
prominent.
intense neovascularization (superficial and deep) in
Eyes that have a faint stain usually do not have any chronic cases. There are varying degrees of edema,
ocular discharge. Eyes that have a dark plaque with usually involving the entire cornea.
surrounding ulceration and intense corneal vascular-
The conjunctiva is usually involved secondary to the
ization often have a mucopurulent ocular dis-
cornea, and may present with a similar white, prolif-
charge.
erative plaque and mucopurulent ocular discharge.
The condition is seen in any breed of cat, but it occurs
The third eyelid may also show proliferative lesions.
predominantly in brachycephalic breeds such as
Persians and Himalayans. There is no sex or age There is often a history of a poor response to a vari-
predilection. ety of antibacterial agents.

Diagnosis
Diagnosis
A tentative diagnosis is based on the history of an ede-
A tentative diagnosis is based on the signalment and
matous, vascularized cornea that will not respond to
clinical signs. Typically there is a mild brown-staining
antibiotic therapy.
cornea to a dense black plaque with keratitis.
Clean the eye with saline or eye wash and take a scrap-
A definitive diagnosis is based on histopathological
ing of the lesion using a scalpel blade, spatula or cytol-
examination of resected cornea. There is a typical
ogy brush. Gently spread the tissue onto a glass
pattern of degenerated stroma surrounded by a ring of
microscope slide and stain with a Wright or
inflammatory cells.
Romanofski stain. The presence of eosinophils is diag-
PCR tests on resected cornea may confirm the pres- nostic. If conjunctival lesions are present, preferably
ence of FHV-1 infection. take a sample from the conjunctiva.