Corneal ulcers and infections
Alternative Names
Bacterial keratitis; Fungal keratitis; Acanthamoeba keratitis; Herpes simplex keratitis
Definition
The cornea is the clear (transparent) tissue at the front of the eye. A corneal ulcer is an erosion or open sore in the outer layer of the cornea. It is often caused by infection.
Causes
Corneal ulcers are most commonly caused by an infection with bacteria, viruses, fungi, or a parasite.
- Acanthamoeba keratitis occurs in contact lens users, especially in people who make their own homemade cleaning solutions.
- Fungal keratitis can occur after a corneal injury involving plant material, or in people with a suppressed immune system.
- Herpes simplex keratitis is a serious viral infection. It may cause repeated attacks that are triggered by stress, esposure to sunlight, or any condition that impairs the immune system.
Corneal ulcers or infections may also be caused by:
- Eyelids that do not close all the way, such as with Bell's palsy
- Foreign bodies in the eye
- Scratches (abrasions) on the eye surface
- Severely dry eyes
- Severe allergic eye disease
- Various inflammatory disorders
Contact lens wear, especially soft contact lenses worn overnight, may cause a corneal ulcer.
Symptoms
Symptoms of infection or ulcers of the cornea include:
- Blurry or hazy vision
- Eye that appears red or bloodshot
- Itching and discharge
- Sensitivity to light (photophobia)
- Very painful and watery eyes
- White patch on the cornea
Exams and Tests
- Examination of scrapings from the ulcer
- Fluorescein stain of the cornea
- Keratometry (measuring the curve of the cornea)
- Pupillary reflex response
- Refraction test
- Slit-lamp examination
- Tests for dry eye
- Visual acuity
Blood tests to check for inflammatory disorders may also be needed.
Treatment
Treatment for corneal ulcers and infections depends on the cause. Treatment should be started as soon as possible to prevent scarring of the cornea.
If the exact cause is not known, patients may be given antibiotic drops that work against many kinds of bacteria.
Once the exact cause is known, drops that treat bacteria, herpes, other viruses, or a fungus are prescribed. Severe ulcers sometimes require a corneal transplant.
Corticosteroid eye drops may be used to reduce swelling and inflammation in certain conditions.
Your health care provider may also recommend that you:
- Avoid eye makeup
- Don't wear contact lenses at all, or don't wear them at night
- Take pain medications
- Wear an eye patch to keep out light and help with symptoms
- Wear protective glasses
Outlook (Prognosis)
Many people recover completely from corneal ulcers or infections, or they have only a minor change in vision.
However, a corneal ulcer or infection can cause long-term damage to the cornea and affect vision.
Possible Complications
Untreated corneal ulcers and infections may lead to:
- Loss of the eye (rare)
- Severe vision loss
- Scars on the cornea
When to Contact a Medical Professional
Call your health care provider if:
- You have symptoms of corneal ulcers or an infection
- You have been diagnosed with this condition and your symptoms become worse after treatment
Prevention
Getting treated for an eye infection by an ophthalmologist right away may prevent ulcers from forming. Wash hands and pay very close attention to cleanliness while handling contact lenses. Avoid wearing contact lenses overnight.
References
Groos Jr. EB. Compliations of Contact Lenses. In: Tasman W, Jaeger EA, eds. Duane's Ophthalmology On DVD-ROM. 1st ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2012: chap 27.
Yanoff M, Cameron D. Diseases of the visual system. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 431.
McLeod SD. Bacterial keratitis. In: Yanoff M, Duker JS, eds. Ophthalmology. 3rd ed. St. Louis, Mo: Mosby Elsevier;2008:chap 4.12.
McLeod SD. Fungal keratitis. In: Yanoff M, Duker JS, eds. Ophthalmology. 3rd ed. St. Louis, Mo: Mosby Elsevier;2008:chap 4.13.
Tuli SS. Herpes simplex keratitis. In: Yanoff M, Duker JS, eds. Ophthalmology. 3rd ed. St. Louis, Mo: Mosby Elsevier;2008:chap 4.15.
Soukiasian S. Peripheral ulcerative keratitis. In: Yanoff M, Duker JS, eds. Ophthalmology. 3rd ed. St. Louis, Mo: Mosby Elsevier;2008:chap 4.16.
Bouchard CS. Noninfectious keratitis. In: Yanoff M, Duker JS, eds. Ophthalmology. 3rd ed. St. Louis, Mo: Mosby Elsevier;2008:chap 4.17.