Microbial Keratitis at an Urban Public Hospital: A 10-Year Update

Microbial keratitis is a potentially eye-threatening infection characterized by a corneal epithelial defect and underlying stromal infiltrate. The clinical course of the infection depends upon both prompt initiation of effective therapy and the particular pathogen involved. 

The classic treatment paradigm for microbial keratitis has been comprehensive evaluation of the eye including gram stain and culture of corneal scrapings followed by empiric treatment with broad spectrum antibiotics, usually two fortified preparations. Treatment can then beappropriately modified when the causative organism(s) are identified and theantibiotic sensitivities are determined.

The availability of highly effective topical ophthalmic fluoroquinolone therapy in the 1990’s has shifted the preferred treatment strategy by most ophthalmologists. Many ophthalmologists no longer culture corneal ulcers on presentation and begin fluoroquinolone monotherapy even when fortified antibiotics are available through local compounding pharmacies. Many studies support the therapeuticequivalence or superiority of fluoroquinolone therapy to fortified antibiotics,which can reduce bacterial load by 99.9% within 24 hours.