Keratitis

Overview

Keratitis is an inflammation of the cornea — the clear, dome-shaped tissue on the front of your eye that covers the pupil and iris. Keratitis may or may not be associated with an infection. Noninfectious keratitis can be caused by a relatively minor injury, by wearing your contact lenses too long or by a foreign body in the eye. Infectious keratitis can be caused by bacteria, viruses, fungi and parasites.

If you have eye redness or other symptoms of keratitis, make an appointment to see your doctor. With prompt attention, mild to moderate cases of keratitis can usually be effectively treated without loss of vision. If left untreated, or if an infection is severe, keratitis can lead to serious complications that may permanently damage your vision.

Symptoms

Signs and symptoms of keratitis include:

• Eye redness
• Eye pain
• Excess tears or other discharge from your eye
• Difficulty opening your eyelid because of pain or irritation
• Blurred vision
• Decreased vision
• Sensitivity to light (photophobia)
• A feeling that something is in your eye

• Causes

  Causes of keratitis include:

  • Injury. If any object scratches or injures the surface of your cornea, noninfectious keratitis may result. In addition, an injury may allow microorganisms to gain access to the damaged cornea, causing infectious keratitis.
  • 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 keratitis. Over-wearing your contact lenses can cause keratitis, which can become infectious.
  • Viruses. The herpes viruses (herpes simplex and herpes zoster) may cause keratitis.
  • Bacteria. The bacterium that causes gonorrhea can cause keratitis.
  • 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 keratitis. 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.

  • Prevention

    Caring for your contact lenses

    If you wear contact lenses, proper use, cleaning and disinfecting can help prevent keratitis. Follow these tips:

    • Choose daily wear contacts, and take them out before going to sleep.
    • Wash, rinse and dry your hands thoroughly before handling your contacts.
    • Follow your eye care professional’s recommendations for taking care of your lenses.
    • Use only sterile products that are made specifically for contact lens care, and use lens care products made for the type of lenses you wear.
    • Gently rub the lenses during cleaning to enhance the cleaning performance of the contact lens solutions. Avoid rough handling that might cause your lenses to become scratched.
    • Replace your contact lenses as recommended.
    • Replace your contact lens case every three to six months.
    • Discard the solution in the contact lens case each time you disinfect your lenses. Don’t “top off” the old solution that’s already in the case.
    • Don’t wear contact lenses when you go swimming.