Definition
Keratoconjunctivitis Sicca is a regular condition of the eye that happens once the tear glands stop manufacturing enough tears to keep the eyes moist, or in a couple of cases, stop manufacturing tears altogether.
Tears are essential in oiling the cornea and removing dirt and other harmful agents that may touch the eye. The tear film contains water, mucus, fatty liquid, all mixed together.
Keratoconjunctivitis Sicca is popularly referred to as “Dry Eye Syndrome” or DES, this condition grows worse and worse, slowly stealing from the animal its eyesight completely.
Keratoconjunctivitis sicca (KCS) as a medical term means swelling of the cornea and its close environs from drying. Dry eye in dogs is a standard condition ensuing from insufficient manufacture of the aqueous portion of the tear film by the lachrymal individually or collectively with the gland of the third eyelid.
Causes
Keratoconjunctivitis Sicca in dogs is commonly caused by some of the following:
- Immune-mediated diseases that damage the tear-producing glands. This is by far the most prominent cause of Keratoconjunctivitis. It is usually inherited. The immune system views the cells that produce a part of the tear film as intruders and attacks fiercely leading to a decline in production.
- Systemic diseases such as canine distemper virus infections.
- Medications such as certain sulphonamides (sulfa drugs).
- Hypothyroidism.
- Nervous system effects of an inner ear infection (neurogenic KCS)
Symptoms
Most dogs with dry eye keratoconjunctivitis sicca have painful, red, and irritated eyes. There is typically a thick, yellowish, mucous-like discharge evident as a result of the decline in the watery part of the tear film.
Ulceration of the cornea is very frequently noticed. In severe cases, there is typically a history of incessant eye injuries, inflammation, or ulcers.
It is also very common to see dogs develop scarring on their cornea known as hyperpigmentation which can be seen upon closer examination.
Corneal scarring resembles a dark film covering the eyes. The small blood vessels are often seen flowing across the membrane referred to as neovascularization.
Vision could also be reduced if scarring is severe. Middle-aged and older dogs are more vulnerable to KCS compared to younger dogs.
Both eyes are usually affected although it is not uncommon for one eye to appear more damaged than the other.
Breed Specific
Keratoconjunctivitis sicca in dogs is very common. More noteworthy is the fact that some breeds are genetically more susceptible. They include: Bulldog, Chihuahua, Toy Poodle, Pug, Chow Chow, Affenpinscher, Dachshund, Shih Tzu, and the Terriers.
Stem Cell Treatment
KCS research started much later compared with other therapeutic uses of stem cells in dogs, such as osteoarthritis. However, results have already shown a clear healing advantage. This fast advancement is mainly due to the relative ease of quantifying therapeutic effectiveness in dogs with keratoconjunctivitis sicca. Unlike assessments of gait, pain, or mobility in osteoarthritis studies, tear production can be easily quantified by a Schirmer tear test, allowing for an objective, reproducible, and easily interpreted efficacy outcome.
Stem cells stop the attack on the tear glands by reconfiguring the immune system. The stem cells are injected into the tear gland and third eye of the dog. The success rate of stem cell treatment is very remarkable.
Studies conducted over the past five years suggest that keratoconjunctivitis sicca treatment with mesenchymal stem cells (MSCs) may allow dogs with mild to moderate KCS to discontinue topical eye medications for at least 1 year, and dogs with severe disease have shown clinically significant improvements after therapy.
