Alternative Names: Bacterial keratitis; Fungal keratitis; Acanthamoeba keratitis; Herpes simplex keratitis

Causes, incidence, and risk factors:

Corneal ulcers are most commonly caused by an infection with bacteria, viruses, fungi or amoebae. Other causes are abrasions or foreign bodies, inadequate eyelid closure, severely dry eyes, severe allergic eye disease, and various inflammatory disorders.

Contact lens wear, especially soft contact lenses worn overnight, may be a precipitating factor. Herpes simplex keratitis is a serious viral infection. It may have recurrences that are triggered by stress, exposure to sunlight, or any condition that impairs the immune system.

Fungal keratitis can occur after a corneal injury involving plant material, or in immunosuppressed people. Acanthamoeba keratitis occurs in contact lens users, especially those who attempt to make their own homemade cleaning solutions.

Risk factors are dry eyes, severe allergies, history of inflammatory disorders, contact lens wear, immunosuppression, trauma, and generalized infection.

Symptoms:

• Eye pain
• Impaired vision
• Eye redness
• White patch on the cornea
• Sensitivity to light (photophobia)
• Watery eyes
• Eye burning, itching and discharge

Signs and tests:

• Visual acuity
• Refraction test
• Tear test
• Slit-lamp examination
• Pupillary reflex response
• Keratometry (measurement of the cornea)
• Scraping the ulcer for analysis or culture
• Fluorescein stain of the cornea

Blood tests to check for inflammatory disorders may also be needed.

Treatment:

Treating corneal ulcers and infections depends on the cause. They should be treated as soon as possible to prevent further injury to the cornea. Broad antibiotic coverage is started and then more specific antibiotic, antiviral, or antifungal eye drops are prescribed (as soon as the agent which causes the ulcer has been identified).

Corticosteroid eye drops may be used to reduce inflammation in certain conditions. Severe ulcers may need to be treated with corneal transplantation.

Support Groups:

Expectations (prognosis):

Untreated, a corneal ulcer or infection can permanently damage the cornea. Untreated corneal ulcers may also perforate the eye, resulting in spread of the infection inside, increasing the risk of permanent visual impairment.

Complications:

• Corneal scarring
• Severe vision loss

Calling your health care provider:

Call your health care provider if you develop impaired vision, severe light sensitivity, or eye pain.

Prevention:

Prompt, early attention by an ophthalmologist for an eye infection may prevent the condition from worsening to the point of ulceration. Wash hands and pay rigorous attention to cleanliness while handling contact lenses, and avoid wearing contact lenses overnight.