Methicillin-resistant Staphylococcus aureus and methicillin-resistant Staphylococcus epidermidis infections in the cornea

Purpose. To describe the incidence and clinical management of corneal infections with methicillin-resistant Staphylococcus aureus (MRSA) or methicillin-resistant Staphylococcus epidermidis (MRSE). Methods. The incidence of methicillin-resistant Staphylococcus (MRS) at the Department of Ophthalmology, Kyoto Prefectural University of Medicine, was reviewed during the 5-year period from January 1996 to December 2000. Clinical aspects of MRS colonization or infection in the eye were investigated. Results. Methicillin-resistant S. aureus or MRSE was detected from 30 eyes with ocular diseases; post-keratoplasty (I I eyes), ocular surface disorders without operation (9 eyes), and others (10 eyes). Among the 30 eyes, 12 manifested keratitis. Eight cases (8 eyes) occurred after keratoplasty, including four postoperative cases in patients with Stevens-Johnson syndrome, and two bilateral cases (4 eyes) in patients with acute-phase Stevens-Johnson syndrome. The degree of MRS keratitis was classified into 4 groups: asymptomatic carrier or conjunctivitis, intraepithelial infiltrations, superficial keratitis, and severe keratitis leading to corneal perforation. All cases of keratitis were treated successfully with topical ofloxacin (OFLX), vancomycin (VCM), or arbekacin (ABK). Conclusion. Factors associated with ocular MRS colonization were long-term use of antibiotics and/or steroids, and hospitalization. Patients who had undergone keratoplasty or who had Stevens-Johnson syndrome were at increased risk of MRS keratitis. Superficial stromal infiltrations, minimal melting, and minimal stromal scarring are characteristic of MRS keratitis. Therapy for MRS keratitis is summarized. Ofloxacin, VCM, and ABK are effective in the treatment of MRS keratitis. Vancomycin eye ointment is effective as the final choice in serious cases.