Daptomycin versus Vancomycin in a Methicillin-Resistant Staphylococcus aureus Endophthalmitis Rabbit Model: Bactericidal Effect, Safety, and Ocular Pharmacokinetics

作者:Lefevre Sophie*; Saleh Maher; Marcellin Luc; Subilia Audrey; Bourcier Tristan; Prevost Gilles; Jehl Francois
来源:Antimicrobial Agents and Chemotherapy, 2012, 56(5): 2485-2492.
DOI:10.1128/AAC.05745-11

摘要

Staphylococcus aureus is a frequent cause of acute endophthalmitis, and infection with this virulent bacterium is often associated with a poor visual outcome. In this study, we investigated the bactericidal efficacy and the safety of intravitreal daptomycin (DAP), a lipopeptide antibiotic with broad-spectrum activity against Gram-positive bacteria, compared with those of intravitreal vancomycin (VAN) in a methicillin-resistant S. aureus endophthalmitis rabbit model. The pharmacokinetics and pharmacodynamics of daptomycin in the infected eyes were also studied. Rabbits were randomly divided into three treatment groups (n = 8) and one untreated group (n = 4), to compare the effect of single intravitreal injections of 0.2 mg and 1 mg of daptomycin (DAP 0.2 and DAP 1 groups, respectively) with that of 1 mg of intravitreal vancomycin (VAN 1 group). Vitreal aspirates were regularly collected and grading of ocular inflammation was regularly performed until euthanasia on day 7. In the DAP 0.2 group, 62.5% of the eyes were sterilized and the mean bacterial count presented a reduction of 1 log unit. In the DAP 1 and VAN 1 groups, the infection was eradicated (100% and 87.5% of eyes sterilized, respectively), with a 4-log-unit reduction of the mean bacterial count. The bactericidal efficacy in the DAP 1 group was not inferior to that in the VAN 1 group and was superior to that of the other regimens in limiting the ocular inflammation and preserving the architecture of the ocular structures (P %26lt; 0.05). The elimination half-life (t(1/2 beta)) of daptomycin was independent of the administered dose (38.8 +/- 16.5 h and 40.9 +/- 6.7 h, respectively, for the DAP 0.2 and DAP 1 groups) and was significantly longer than the t(1/2 beta) of vancomycin (20.5 +/- 2.0 h for the VAN 1 group) (P %26lt; 0.05). This antibiotic could therefore be considered for the treatment of intraocular infections caused by Gram-positive bacteria.

  • 出版日期2012-5