Author(s): Dajcs JJ, Thibodeaux BA, Marquart ME, Girgis DO, Traidej M, O’Callaghan RJ. Effectiveness of ciprofloxacin, levofloxacin, or moxifloxacin for treatment of experimental Staphylococcus aureus keratitis. Antimicrob Agents Chemother. 2004 Jun;48(6):1948-52. PMID 15155183
Journal: Antimicrobial Agents And Chemotherapy, Volume 48, Issue 6, Jun 2004
The purpose of this study was to quantitatively compare, in a rabbit keratitis model, the levels of effectiveness of moxifloxacin, levofloxacin, and ciprofloxacin for the treatment of Staphylococcus aureus isolates of diverse antibiotic susceptibilities. Rabbit eyes were intrastromally injected with approximately 100 CFU of methicillin-sensitive or methicillin-resistant S. aureus (MSSA or MRSA, respectively) organisms that were either sensitive or resistant to ofloxacin. One drop of moxifloxacin (0.5%), levofloxacin (0.5%), or ciprofloxacin (0.3%) was topically applied hourly from 4 to 9 (early) or 10 to 15 (late) h postinfection. At 1 h after cessation of therapy, the corneas were harvested, and the number of CFU per cornea was determined. For the ofloxacin-sensitive strains, early treatment of MSSA or MRSA with moxifloxacin, levofloxacin, or ciprofloxacin produced approximately a 5-log decrease in CFU per cornea relative to that in untreated eyes (P </= 0.0001). For late therapy of ofloxacin-sensitive strains, moxifloxacin, levofloxacin, and ciprofloxacin produced approximately 5-, 4-, and 2- to 3-log reductions in CFU per cornea, respectively (P /=4-log or >/=3-log decrease, respectively, in the MSSA or MRSA strains (P /= 0.3627), whereas moxifloxacin produced a significant reduction in CFU per cornea of approximately 1 log (P </= 0.0194). Therefore, for three of the four treatments tested, moxifloxacin demonstrated greater effectiveness than either levofloxacin or ciprofloxacin.