A case of Stenotrophomonas maltophilia keratitis effectively treated with moxifloxacin

A 70-year-old man with a long history of diabetes mellitus presented to our hospital (Department of Ophthalmology, Sahm Yook Medical Center, Seoul, Korea) complaining of severe ocular pain and visual disturbance in his left eye that had started three days prior to admission. A round 3.7 × 5.0 mm dense central stromal infiltrate with an overlying epithelial defect was noted on slit-lamp examination. Following corneal scrapings and culture, topical 0.5% moxifloxacin and 0.5% tobramycin were administered hourly. A few days later, Stenotrophomonas maltophilia was isolated in a bacterial culture from a corneal specimen. According to the results of susceptibility tests, topical 0.5% moxifloxacin was given every hour and 0.5% tobramycin was stopped. The patient's clinical features improved steadily with treatment. The corneal epithelium healed rapidly, and the infiltrate resolved within four weeks of the initiation of treatment. The patient's best corrected visual acuity improved from hand motion to 20 / 25.