Keratitis

What is keratitis?

Keratitis is the medical name for inflammation of the cornea, the clear window that covers the iris and the pupil in your eye. Keratitis may cause a corneal ulcer.

Keratitis can be divided into two categories based on cause: infectious keratitis or noninfectious keratitis. Some people call infectious keratitis “microbial” keratitis.

Early signs and symptoms of keratitis include eye pain and redness. If you think you may have keratitis, you should see a healthcare provider immediately. Damage to your eyes from the disease can result in vision loss. Worldwide, keratitis causes most cases of corneal blindness.

How common is keratitis?

Keratitis is a common condition that can be treated. However, outside of the U.S. and other developed countries, infectious keratitis is a significant cause of blindness. Some of the infections that cause keratitis can be transferred from person to person by touching contaminated items, coughs or sneezes.

What are the signs and symptoms of keratitis?

Signs and symptoms of keratitis include:

• Eye pain.
• Watery eyes.
• Red, irritated and bloodshot eyes.
• Sensitivity to light (photophobia).
• Blurry vision.
• Problems opening your eyelid.
• Feeling like something is in your eye.

What causes keratitis?

There are infectious and noninfectious causes of keratitis.

What causes infectious keratitis?

Causes of infectious keratitis include:

• Bacterial keratitis: This type, caused by bacteria, is the most common.
• Fungal keratitis: This type is caused by fungi, often from plants.
• Parasitic keratitis: Parasites are organisms that live off another organism. Acanthamoeba keratitis is caused by a one-celled parasite called an amoeba.
• Viral keratitis: Viruses like the ones that cause shingles and herpes simplex can cause keratitis. Herpes simplex keratitis often recurs.

What causes noninfectious keratitis?

Causes of noninfectious keratitis include:

• Injuring your eye. (This includes having eye surgery, being in an accident and having a condition where your eyelashes scrape against the surface of your eye.)
• Wearing contact lenses for too long.
• Having a foreign object in your eye.
• Being exposed to ultraviolet (UV) light for too long.
• Having a vitamin A deficiency.
• Having an eyelid disorder or immune system condition that causes dry eyes.

What are risk factors for developing keratitis?

Anyone can develop keratitis. However, one major risk factor for keratitis is wearing contact lenses. This is related to:

• Wearing them longer than you’re supposed to wear them. This can cause damage to your eye and possibly allow infection to enter.
• Not cleaning / disinfecting them properly.
• Wearing them while you’re in pools, hot tubs or outdoor water sources.

Other risk factors include:

• Using corticosteroids over a long period of time.
• Having a weakened immune system.
• Having dry eyes.
• Having an injury to your eyes, including surgery.

How is keratitis diagnosed?

Your eye care provider will first ask you questions about your symptoms and medical history. Then they’ll do some or all of these tests:

• A complete eye exam: Your provider will use bright lights and a microscope to look at your eyes.
• A culture of discharge from your eye: Your provider will send a swab with the discharge to a lab for identification.
• Fluorescein stain test: Your provider will put dye into your eye and then look at it with a blue lamp.

How is keratitis treated?

If you have a mild case of keratitis, your provider may suggest using lubricant eye drops and letting your eye heal on its own.

However, medication normally treats infectious keratitis. If you have a bacterial infection, you’ll get antibiotic eye drops. If you have a fungal infection, the eye drops will contain antifungal medication. If you have a virus, your provider will prescribe antiviral eye drops.

After a bacterial or viral infection clears up mostly or completely, your provider might suggest steroid eye drops to reduce swelling.

For pain, your provider might give you eye drops that dilate your eye.

If you have advanced keratitis, you may need oral medication to treat infections.

If you don’t respond to medication and keratitis is causing scars on your cornea, you may need a cornea transplant.

How soon after treatment will I feel better?

You’ll probably start feeling better after one or two days if you’re taking anti-infective medication. Recovery will take longer for more severe cases.

How can I reduce my risk of developing keratitis?

You can reduce your risk of developing keratitis by:

• Following instructions on how long to wear your contact lenses.
• Making sure your hands are clean if you have to touch your eyes.
• Following instructions on cleaning and sanitizing your contact lenses.
• Not swimming, showering or using the hot tub when you’re wearing your contact lenses.
• Practicing good hand washing techniques and avoiding contact with people who are sick.
• Wearing protective eyewear while working and participating in sports.
• Wearing sunglasses to protect your eyes from UV light.

What can I expect if I have keratitis?

If you have most types of keratitis, treatment cures it. If you have a viral form of keratitis, it may come back.

You may develop glaucoma as a result of infectious keratitis. The outlook for people with fungal keratitis may be worse than the outlook for people with bacterial keratitis.

Without treatment, keratitis causes scarred corneas that can lead to vision loss.

When should I see my healthcare provider?

You should always contact your healthcare provider if you have eye pain along with redness, eye watering and blurred vision.

If you received treatment and you aren’t recovering, you should contact your provider.

What questions should I ask my doctor about keratitis?

You may want to ask your provider questions like these:

• What type of keratitis do I have?
• When can I return to work or school?
• Is it safe for me to drive?
• How can I reduce stress so that herpes simplex keratitis doesn’t flare up?
• What complications should I look for and when should I contact you?

Keratitis vs. uveitis: what’s the difference?

The difference between uveitis and keratitis has to do with the location of the inflammation. Signs and symptoms are similar, but uveitis affects the uvea.

The uvea is the middle layer of the eye that includes the iris, the choroid and the ciliary body. Keratitis affects your cornea, the protective layer over your iris.

Another eye condition with similar symptoms is pink eye (conjunctivitis). It affects the conjunctiva (tissues lining the eyelid).

You could have keratoconjunctivitis if the inflammation affects both the cornea and the conjunctiva. Children often get a mild form of this condition.

A note from Cleveland Clinic

With keratitis, like other eye conditions, it’s important to get medical help early. Contact a healthcare provider any time you have eye pain, especially if you also have redness, swelling, a problem opening your eye or blurry vision. Keratitis treatment is available.