A corneal ulcer is an inflammatory and ulcerative keratitis. Common infectious etiologies include bacteria (Staphylococcus, Streptococcus, Pseudomonas) and viruses (HSV, adenovirus). Bacterial corneal ulcers are commonly associated with extended-wear contact lenses. Rare causes of corneal ulcers include fungal infections and Acanthamoeba, a ubiquitous protozoan associated with contaminated contact lens solutions. Fungal infections may also arise from trauma involving vegetable matter such as a tree branch. Acanthamoeba infections may also occur from swimming in lakes, especially while wearing contact lenses.
Patients present with pain, photophobia, decreased vision, discharge, and a foreign-body sensation. Ocular findings include a corneal infiltrate, typically a round white spot, with conjunctival hyperemia, meiosis, and chemosis. Slit-lamp biomicroscopy may demonstrate an epithelial defect with fluorescein uptake. Anterior chamber findings can include cells and flare, keratic precipitates, and a hypopyon.
Management and Disposition
Corneal ulcers are an ophthalmologic emergency requiring emergent ophthalmology consultation. Stains and cultures should be obtained as expeditiously as possible. Intensive topical treatment using fortified antibiotics is the most effective treatment route, initially given every 30 to 60 minutes. For mild cases, a single fluoroquinolone agent may suffice. For more severe cases, dual therapy using a cephalosporin or vancomycin combined with an aminoglycoside is recommended. Clinical improvement is usually noted after 2 to 3 days. Systemic antibiotics are used in cases where the sclera is involved (Pseudomonas) or if there is a high risk of concurrent systemic disease (Neisseria, Haemophilus). Cycloplegics are recommended if there is an accompanying iritis. Steroids and eye patching are contraindicated. A contact lens wearer must discontinue contact lens wear.
A corneal ulcer is an ophthalmologic emergency.
Extended-wear contact lens use is a risk factor for corneal ulcer.
Pseudomonas aeruginosa, associated with thick yellow-green or blue-green mucopurulent tenacious exudate, is capable of destroying the cornea within 6 to 12 hours.
Acanthamoeba should be suspected in contact lens wearers with contaminated lens solutions or who swim wearing their contact lens. Classically, these patients have pain out of proportion to their clinical findings.
Infectious ulcers tend to develop centrally, away from the vascular supply and immune system of the limbus.
Corneal Ulcer. An elliptical ulcer at 5-o’clock position near the limbus is seen. This location is atypical for a bacterial ulcer. The patient presented with painful red eyes and normal uncorrected vision, but wore cosmetic soft contact lenses. Bilateral corneal ulcers were diagnosed, which cleared after treatment with topical ciprofloxacin. Note that the ciliary flush seen in the nasal portion of the limbus is not to be mistaken for conjunctivitis. (Photo contributor: Kevin J. Knoop, MD, MS.)
Corneal Ulcer. A white circular corneal infiltrate is seen in the central visual axis in this contact lens ...