Activity of Oxacillin versus Vancomycin against Oxacillin-Susceptible mecA-Positive Staphylococcus aureus Clinical Isolates by Population Analyses, Time-Kill Assays and a Murine Thigh Infection Model.
Antimicrob Agents Chemother. 2012 Mar 19;
Authors: Labrou M, Michail G, Ntokou E, Pittaras TE, Pournaras S, Tsakris A
Abstract
We tested the activity of oxacillin compared with vancomycin, against 15 oxacillin-susceptible MRSA clinical isolates (OS-MRSA). By population analyses 6 OS-MRSA grew up to 8 ?g/ml and 9 isolates 12 to >32 ?g/ml dicloxacillin and all isolates up to 2 ?g/ml vancomycin. Both drugs exhibited similar bactericidal activity. In experimental infections, the therapeutic efficacy of dicloxacillin was significant (P <0.05 vs. untreated controls) in 10 OS-MRSA and vancomycin was effective (P <0.05) against 12 isolates; dicloxacillin had comparable efficacy with vancomycin (P >0.05) in 8 isolates. The favorable response to dicloxacillin treatment might suggest anti-staphylococcal penicillins against OS-MRSA infections.
PMID: 22430957 [PubMed - as supplied by publisher]