Keratoconjunctivitis sicca (KCS) is a Latin medical term used to describe a condition of decreased tear production. The term technically means "inflammation of the cornea and conjunctiva from drying." When the watery part of the tears is not produced in adequate amounts, the eye becomes chronically inflamed, and scarring and pigmentation of the cornea may lead to a decrease in vision. Another commonly used term to describe this disease is "dry eye."
Numerous breeds of dogs are at risk for developing KCS including the West Highland white terrier, English
bulldog, pug,
shih tzu, American cocker spaniel, Lhasa apso and Pekingese.
If left untreated, KCS is a potentially vision threatening disease. It may lead to painful corneal ulcerations in the acute stage of the disease. In chronic KCS, vision may be impaired because of scarring of the cornea.
Causes The most common cause of KCS in dogs is an immune-mediated destruction of the tear glands. This cause occurs in female dogs more often than male dogs, and is more common certain breeds, such as the American cocker spaniel, English bulldog, Lhasa apso, and West Highland white terrier.
Other causes of KCS include a rare side-effect of certain medications (especially sulfonamide containing drugs), removal of a prolapsed gland of the third eyelid, infections (such as canine distemper), chronic inflammation of the conjunctiva, trauma to the tear glands, and certain skin diseases and neurological disorders.
Animals with low thyroid hormone output (hypothyroidism) are also predisposed to KCS.
What to Watch For
Chronic redness of the eye
Chronic thick, yellow-green discharge, especially in the morning
The development of a film over the cornea
Decreased vision in predisposed breeds
Diagnosis
Veterinary care includes diagnostic tests and subsequent treatment recommendations.
A thorough physical examination is an important part of diagnosing the cause of the KCS, but the disease is actually confirmed during the eye examination.
A Schirmer tear test is performed to determine the amount of watery tears produced by the eyes.
In addition, fluorescein staining of the eye is also performed to detect any corneal ulcers.
The degree of corneal cloudiness and scarring are assessed and the interior of the eye is also examined.
Treatment
The intensity of the treatment depends on the severity of the disease. It may include one or more of the following medications:
Application of 0.2% cyclosporine ointment twice a day or a compounded solution of 1% or 2% cyclosporine if the commercial ointment is not available
Artificial tear solution applied often during the day
Artificial tear ointment applied 1 to 4 times daily
Antibiotic ointment or drops if a corneal ulcer or infection are present
Antibiotic-corticosteroid drops or ointment if inflammation and scarring are present
Surgery rarely in unresponsive cases
Home Care and Prevention
Once diagnosed, home care is an important part of treatment. Keeping the eyes clean and free of discharge can be challenging. Eye discharge is common and can be very sticky and hard to remove. Applying a warm compress to the eye for a few minutes may make it easier to remove the discharge. The discharge may also be removed from the eye by carefully rinsing the eye with an irrigating eye solution that can be bought over the counter at a drug store.
Apply all medication as directed, and notify your veterinarian if you are having difficulty treating your pet. When treating your animal with both drops and ointment, use any drops first, followed by the ointment.
Monitor the eye for changes such as increased discharge, squinting or redness, or if your pet starts rubbing or scratching at his eye. Notify your veterinarian immediately.
It is difficult to prevent KCS, but early treatment is crucial. It is very important to take your pet to your veterinarian when you notice persistent discharge and redness. When diagnosed early in the disease, the long-term prognosis for vision is much better than when the KCS is diagnosed in a late stage of the disease.