Keratitis is an inflammation of the clear outer layer at the front of the eye, which lies directly in front of the coloured part of the eye (the iris) and the pupil, called the cornea.
The condition is most commonly caused by an infection of the cornea, which is often related to wearing contact lenses. It can also be caused by a number of microorganisms such as bacteria, viruses, parasites or fungi. However, keratitis can occur without an infection.
It is a serious condition that needs emergency treatment by an eye doctor (ophthalmologist) to stop it from progressing and causing lead to permanent loss of vision. If you think you may have keratitis, or you are unsure, see your doctor immediately or go to the nearest hospital.
Infective keratitis usually causes a painful, red eye. The pain can be severe in some cases.
Bacterial keratitis often develops suddenly. An ulcer may develop on the surface of the cornea which can look like a small white or yellow spot on the front of your eye.
Keratitis is also associated with the following symptoms:
- sensitivity to light
- watering of the eyes
- discharge from the eye
- vision changes (blurred vision or loss of vision)
- eyelid swelling
- eye irritation, a gritty or burning sensation
Your doctor may suspect keratitis based on your symptoms, an examination of your eyes, and by testing your vision.
If you wear contact lenses, your doctor is likely to ask you about when and how you use them. You should also take your contact lenses, storage box, and cleaning solution with you when you see the doctor. These may be tested for infection.
Because keratitis must be urgently treated to prevent loss of vision, your doctor is likely to refer you as an emergency to an eye specialist (ophthalmologist).
Your ophthalmologist may examine your eyes further. This may involve:
- looking at the back of the eye using a slit lamp (a microscope using a bright beam of light)
- taking a small sample of cells from the surface of your eye (a corneal scrape) to test for any infection
- measuring your eye fluid pressure levels
Less commonly, your ophthalmologist may also recommend blood tests to check your immune system and for signs of infection.
Keratitis is a serious condition that can lead to loss of vision if not treated quickly. You will need to see an ophthalmologist on the same day.
The exact treatment you receive will usually depend on the type of keratitis you have.
Your doctor will usually begin treating you before they know the exact cause of the keratitis, usually with antibacterial eye drops. Once the test results come back, your treatment may then be adjusted.
The treatment options for keratitis may include:
- antibiotic eye drops (tablets in some cases) for bacterial keratitis and initially for other types of infectious keratitis
- antifungal eye drops and tablets for fungal keratitis
- antiviral eye drops/ointment and tablets for viral keratitis
- antiseptic drops for Acanthamoeba keratitis
- steroid eye drops, depending on the type of keratitis
- oral painkillers, to relieve any pain
- pupil dilating drops, to relieve any light sensitivity
- an eye shield for serious cases, where the cornea starts to thin
- surgery – laser surgery or a corneal transplant if there is serious corneal scarring and/or permanent loss of vision
You may be admitted to hospital for treatment, especially if you have a serious infection or you are likely to struggle to closely follow your treatment plan at home.
If you wear contact lenses, you will need to stop doing so until your doctor tells you it is safe to start using them again.
The risk of keratitis complications depends on the type of keratitis you have, its severity, and how quickly you get medical attention.
The most common complications include:
- corneal perforation (a hole in the cornea)
- inflammation of the internal eye tissues (commonly caused by an infection)
- corneal scarring
Most of these conditions are serious, can cause loss of vision, and may need surgical treatment.
Keratitis is commonly associated with wearing contact lenses. Therefore maintaining good hygiene when using contact lenses is important in preventing keratitis.
If you wear contact lenses, you can reduce your risk of keratitis by:
- removing your contact lenses overnight
- wearing your contact lenses for no longer than recommended by your eye doctor each day
- washing your hands thoroughly when putting in and taking out your contacts
- replacing your lens case frequently
You can also minimise your risk of infectious and non-infectious keratitis by:
- using protective eyewear during dangerous activities
- seeking medical attention immediately after any eye injury
- getting treatment for conditions that increase your risk of keratitis, such as dry eye and ingrown eyelashes
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Keratitis is a serious condition that requires prompt treatment in most cases to avoid permanent loss of vision. If you think you have keratitis or are not sure, see a doctor or go to the nearest hospital immediately.
If you have suffered from keratitis, you may find it helpful to share your experience with others who have had the condition. Ask your doctor for information about useful support groups.
To find answers to any other health questions you might have, visit our Health A-Z.