Like pinkeye (conjunctivitis), keratitis is a similar disease of the eye which causes inflammation. Our cornea, that center portion of the eye surrounding the pupil, turns red and becomes extremely sensitive to light.
There are almost 50,000 cases of keratitis diagnosed in the United States each year, making it the most widely-known infectious disease of the eye and the most common reason for corneal blindness in the country.
KERATITIS CAUSESOur body is normally geared to fight off infections, and in this case, the duration of a keratitis infection can generally be cut short, especially when treated with antibiotics. However, if keratitis is caused by an injury to the eye or a rheumatic disease, the infection can take a long time to heal, sometimes even becoming a chronic or constant illness.
There are two kinds of keratitis. The superficial kind affects the outer layers of the cornea and normally heals without leaving a scar. Deep keratitis infects the deeper layers of the cornea, and may cause scarring and impaired vision. If left untreated, keratitis can cause permanent damage and loss of eyesight.
There are different types of keratitis depending on the cause. The most common comes from the very same virus that causes cold sores – the herpes simplex virus type 1. This type of infection starts at the cornea’s outer layer, resulting in pain, reddening of the membrane surrounding the eye (conjunctiva), light sensitivity, watery and blurred vision, and a gritty sensation which will feel like sand in the eye.
This type of keratitis can occur repeatedly due to any remaining virus, fatigue, stress or frequent exposure to ultraviolet light, as when skiing, swimming or boating. With repeat infections, the eye develops lesions which take on the pattern of the veins in a leaf, or dendritic keratitis, which result in sores, lasting scars, and corneal numbness.
When the disease stems from the herpes simplex virus, the infection may be isolated to one eye. But if caused by other reasons, both eyes are liable to be affected.
KERATITIS DIAGNOSISAnother type of keratitis is caused by bacteria. Bacterial keratitis sufferers usually wake up with their eyelids stuck together because of pus and excessive tearing. There will be accompanying pain and redness, light sensitivity, blurry vision, and a clouding of your cornea. Bacterial keratitis usually stems from incorrect use of contact lenses. Studies have shown that leaving soft contact lenses in the eye overnight can increase the risk of acquiring bacterial keratitis. Using contaminated eye makeup can also make you susceptible to this type of the disease.
On the other hand, if your immune system has been weakened from a previous viral infection, you are likely to get fungal keratitis. This slowly developing type of infection comes from parasites, fungi, moulds, dust, yeast, pollen, or wherever there is an abundance of plants or plant material.
When you have peripheral ulcerative keratitis, you can be sure that it has been caused by inflammation and dryness brought about by rheumatoid arthritis, chronic polychondritis (inflammation of the connective tissues), and Wegener’s granulomatosis (a rare kidney-related disease which also causes nodules to sprout in the respiratory tract).
Other types of the disease include superficial punctuate keratitis, caused by adenoviruses, the main culprits of upper respiratory tract infections; Acanthamoeba keratitis, which is a painful condition where the cornea secretes a large amounts of pus; photokeratitis, or snowblindness, caused by too much exposure to the UV light from suntanning lamps, water sports, or welding arcs; and interstitial keratitis, a rare type of infection associated with syphilis.
In some instances, keratitis can come from a Vitamin A deficiency, unsanitary surroundings, eye dryness due to eyelid disorders or an inability to produce tears, and foreign objects that become stuck in the eye, causing injury.
If you catch a keratitis infection, you may likely mistake it for conjunctivitis (pinkeye) because of the remarkable similarity of symptoms. The cornea and conjunctiva become red and inflamed, and the eye will feel great discomfort as if a foreign particle were in it. The affected eye will also experience photophobia, or sensitivity to bright light. As the infection progresses and the disease becomes more severe, there will be a lot of pain and pus formation. Blurring from excess tears and loss of vision can be expected at this point.
Some cases of chronic keratitis can result in complications like glaucoma (an eye disease which damages the optic nerve), cornea ulceration, permanent scarring of the eye, and finally blindness.
As soon as you start showing any symptoms of keratitis, it is important to consult your doctor immediately, especially if you start experiencing pain or blurry vision. An experienced ophthalmologist or optometrist will help you determine whether you do indeed have keratitis, an infection which is most commonly mistaken for conjunctivitis.
Your eye specialist will assess your symptoms and your general health, as well as your medical history. Expect your doctor to use a magnifying instrument to examine the surface of your cornea to look for traces of a viral infection, usually revealed by the presence of small ulcers with starlike branches, or tiny blisters like cold sores on your eyelid.
The doctor is also likely to administer a vision test to measure the sharpness and clearness of your eyesight, as well as examining the way your pupil reacts to light. Your cornea will be measured, and your doctor will use a special instrument known as a slit lamp to further check the extent of infection in your eye. To make a definite diagnosis of keratitis, your eye will be swabbed, and samples of pus or fluid will be taken for laboratory examination.
KERATITIS TREATMENTTreating your keratitis will depend on what has caused it. If you have the infectious kind, your doctor may prescribe antibiotics, antibacterial or antiviral eye drops, antifungal pills or even an intravenous drip. Your doctor will strongly advise you not to use topical cortiscosteriods or any eye medications containing steroids, like neomycin+polymyxin+dexamethasone (Maxitrol), as they will only worsen the infection and cause vision loss.
If you wear contact lenses, your opthalmologist will likely advise you to remove them until the infection subsides, or get rid of contaminated lenses and their cases. There are many generic antibacterial solutions available, like levoflaxin (Quixin), gatifloxacin (Zymar), moxifloxacin (Vigamox), and ofloxacin (Ocuflox) for effective contact lens cleaning, and to prevent a recurrence of keratitis.
Although antiviral therapy can treat keratitis caused by the herpes simplex virus, the infection can reappear if some of the virus remains system. Your doctor will apply anesthetic drops to the affected eye, and lightly scrape away infected tissue from your cornea. This will mean having to wear an eye patch for about a week. Expect your eye specialist to prescribe soft contact lenses to protect your eye until the infection heals. In some severe cases, you will have to undergo surgery to replace a damaged cornea.
If your infection is related to a rheumatic disease like rheumatoid arthritis, your doctor will advise treating the arthritis itself, while keeping the eye moist with eye drops. Keratitis caused by ocular dryness can be remedied by artificial tears to lubricate the cornea, while vitamin supplements are effective in treating keratitis that results from a Vitamin A deficiency.
KERATITIS PREVENTIONPreventing keratitis can be as simple as maintaining a well-balanced diet with an adequate amount of Vitamin A, or regularly taking Vitamin A supplements. Since keratitis comes from the same virus that causes cold sores, avoid bringing your fingers to your eyes if you do have a cold sore, to prevent the infection from spreading.
If you wear contact lenses, be sure to practice proper lens cleaning hygiene, and wear protective glasses if you work in an environment which involves eye hazards, like welding in construction. If your eyes feel dry, use lubricating eye drops as this can prevent the occurrence of keratitis stemming from other causes.
It is important to have any symptoms of keratitis diagnosed as early as possible. The earlier treatment is started, the more effective it will be in preventing further eye damage. Keratitis caused by rheumatic diseases or a Vitamin A deficiency can be cured by treating the underlying cause.
If you wear contact lenses on a daily basis, it is also important to be careful about your contact lens solution. Some solutions have actually been recalled for actually causing keratitis. In May 2007, Centers for Disease Control and Prevention (CDC) linked an outbreak of keratitis to the use of an Advanced Medical Optics product, the Complete MoisturePlus Solution, a lens solution which was recalled for resulting in numerous cases of Acanthamoeba keratitis.
In more positive news, the National Eye Institute (NEI) has made advanced developments in field of eye research. In June 2007, scientists made the discovery of an antiviral drug which taken orally, can greatly diminish the recurrence of keratitis caused by the herpes simplex virus. It was also found to keep the more severe corneal stromal keratitis from returning.