Keratitis

Alternative Names

Keratitis interstitial

What is Keratitis

Keratitis is an inflammation or infection of the cornea of the eye. The cornea is the clear, dome-shaped surface that covers the front of the eye.

It is a medical emergency because extensive involvement may lead to blindness.

Signs and symptoms

The symptoms of keratitis usually include:

• pain
• tearing
• blurring of vision

The pain may be mild to severe, depending on the cause and extent of the inflammation. There is also may be sensitivity to light. To the observer, the eye may appear red, watery, and if the cornea has extensive keratitis, the normally clear cornea may look gray or have white to gray areas.

Possible complications

Possible complications of keratitis include:

• Chronic corneal inflammation
• Chronic or recurrent viral infections of cornea
• Open sores on cornea (corneal ulcers)
• Corneal swelling and scarring
• Temporary or permanent reduction in vision
• Blindness

What causes

• Injury. If an object scratches the surface of one of your corneas or penetrates a cornea, keratitis may result without any infection. An injury may also allow bacteria or fungi to gain access to the cornea through the damaged surface, causing keratitis that involves an infection.
• Infected contact lenses. Bacteria, fungi or parasites including the microscopic parasite acanthamoeba may inhabit the surface of a contact lens and contaminate the cornea when the lens is in your eye, resulting in infectious keratitis.
• Viruses. Viruses such as the herpes virus and the virus that causes chlamydia may cause keratitis.
• Polluted water. Bacteria and fungi in water including oceans, rivers, lakes and hot tubs can enter your eyes when you're swimming or bathing and result in keratitis. Even if you're exposed to these bacteria and fungi, a healthy cornea is unlikely to become infected unless there has been some physical breakdown of the delicate surface tissue of the cornea (corneal epithelium). For example, physical breakdown of the corneal epithelium can be caused by wearing a contact lens too long, making the cornea vulnerable to infectious keratitis.

Prevention

Reduction of the main risks of keratitis can be through the use of safety precautions to avoid eye injury, careful contact-lens care including proper cleaning of contact lens cases, and the prompt treatment of early ocular symptoms.

Treatment

Treatment depends on the cause of the keratitis. Infectious keratitis generally requires antibacterial, antifungal, or antiviral therapy to treat the infection. This treatment can involve:

• eye drops
• pills
• intravenous therapy

You should remove any corneal or conjunctival foreign body. Wetting drops may be used if disturbance of the tears is suspected to be the cause of the keratitis. Steroid drops may often be prescribed to reduce inflammation and limit scarring. This must be done carefully and judiciously, since some infections can be worsened with their use.

If you wear contact-lens it is needed to discontinue, whether or not the lenses are related to the cause of the keratitis.