ABSTRACT – Keratitis is an inflammation of cornea which is the outermost layer of the eye that protects it...
Keratitis is an inflammation of the cornea — the clear, dome-shaped tissue on the front of your eye that covers the pupil and iris. It may or may not be associated with an infection. Noninfectious can be caused by a relatively minor injury, by wearing your contact lenses too long or by a foreign body in the eye. Infectious can be caused by bacteria, viruses, fungi and parasites.
If you have eye redness or other symptoms, make an appointment to see your doctor. With prompt attention, mild to moderate cases of this disease can usually be effectively treated without loss of vision. If left untreated, or if an infection is severe, this can lead to serious complications that may permanently damage your vision.
Signs and symptoms of this disease include:
Excess tears or other discharge from your eye
Difficulty opening your eyelid because of pain or irritation
Sensitivity to light (photophobia)
A feeling that something is in your eye
Injury. If any object scratches or injures the surface of your cornea, noninfectious may result. In addition, an injury may allow microorganisms to gain access to the damaged cornea, causing infectious disease.
Contaminated contact lenses. Bacteria, fungi or parasites — particularly the microscopic parasite acanthamoeba — may inhabit the surface of a contact lens or contact lens carrying case. The cornea may become contaminated when the lens is in your eye, resulting in infectious disease. Over-wearing your contact lenses can cause this disease, which can become infectious.
Viruses. The herpes viruses (herpes simplex and herpes zoster) may cause this disease.
Bacteria. The bacterium that causes gonorrhea can cause this disease.
Contaminated water. Bacteria, fungi and parasites in water — particularly in oceans, rivers, lakes and hot tubs — can enter your eyes when you’re swimming and result in this disease. However, even if you’re exposed to these bacteria, fungi or parasites, a healthy cornea is unlikely to become infected unless there has been some previous breakdown of the corneal surface — for example, wearing a contact lens too long.
Contact lenses. Wearing contact lenses — especially sleeping in the lenses —increases your risk of both infectious and noninfectious disease. The risk typically stems from wearing them longer than recommended, improper disinfection or wearing contact lenses while swimming.
It is more common in people who use extended-wear contacts, or wear contacts continuously, than in those who use daily wear contacts and take them out at night.
Reduced immunity. If your immune system is compromised due to disease or medications, you’re at higher risk of developing this disease.
Corticosteroids. Use of corticosteroid eyedrops to treat an eye disorder can increase your risk of developing infectious disease or worsen existing disease.
Eye injury. If one of your corneas has been damaged from an injury in the past, you may be more vulnerable to developing keratitis.
Treatment of noninfectious keratitis varies depending on the severity. For example, with mild discomfort from a corneal scratch, artificial tear drops may be the only treatment. However, if keratitis is causing significant tearing and pain, a 24-hour eye patch and topical eye medications may be necessary.
Treatment of infectious keratitis varies, depending on the cause of the infection.
Bacterial keratitis. For mild bacterial keratitis, antibacterial eyedrops may be all you need to effectively treat the infection. If the infection is moderate to severe, you may need to take oral antibiotics to get rid of the infection.
Fungal keratitis. Keratitis caused by fungi typically requires antifungal eyedrops and oral antifungal medication.
Viral keratitis. If a virus is causing the infection, antiviral eyedrops and oral antiviral medications may be effective. Other viruses need only supportive care such as artificial tear drops.
Acanthamoeba keratitis. Keratitis that’s caused by the tiny parasite acanthamoeba can be difficult to treat. Antibiotic eyedrops are used, but some acanthamoeba infections are resistant to medication. Severe cases of acanthamoeba keratitis may require a cornea transplant.
If keratitis doesn’t respond to medication, or if it causes permanent damage to the cornea that significantly impairs your vision, your doctor may recommend a cornea transplant.