A 15-year-old girl was referred for corneal evaluation after four days of red eye. The patient had slept in her contact lenses four days prior. Slit-lamp biomicroscopy revealed an epithelial defect surrounding a heart-shaped infiltrate. There was mild microcystic edema surrounding the epithelial defect and trace anterior segment inflammation.

Gram stains taken on the day of evaluation revealed many gram-variable rods, which eventually developed into colonies of Serratia marcescens. The patient was managed on a combination of moxifloxacin HCl ophthalmic solution and fortified vancomycin and tobramycin initially, and then only moxifloxacin and fortified tobramycin after culture results were obtained.

Serratia marcescens is a microorganism that can cause corneal or conjunctival infections.

Written by Julie Tsai, MD, Michael P. Kelly, CRA, and Edward J. Holland, MD.

Blink is edited by Richard E. Hackel, MA, CRA, FOPS.