Corneal ulcers are most commonly due to infection by bacteria, viruses, fungi, or amebas. Noninfectious causesall of which may be complicated by infection—include neurotrophic keratitis (resulting from loss of corneal sensation), exposure keratitis (due to inadequate lid closure), severe dry eye, severe allergic eye disease, and various inflammatory disorders that may be purely ocular or part of a systemic vasculitis. Delayed or ineffective treatment of corneal ulceration may lead to devastating consequences with corneal scarring or intraocular infection. Prompt referral is essential.

Patients complain of pain, photophobia, tearing, and reduced vision. The eye is red, with predominantly circumcorneal injection,

there may be purulent or watery discharge.

The corneal appearance varies according to the underlying cause.

» When to Refer

Any patient with an acute painful red eye and corneal abnormality should be referred emergently to an ophthalmologist. Austin A et al. Update on the management of infectious keratitis.