Combined antibacterial effects of between meropenem and vancomycin, teicoplanin, linezolid, or arbekacin in methicillin-resistant Staphylococcus aureus

Abstract

In vitro interaction between meropenem (MEPM) and vancomycin (VCM), teicoplanin (TEIC), linezolid (LZD), or arbekacin (ABK) was studied using the checkerboard technique in 207 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA)(MIC of MEPM≥32). Of 207 strains, synergistic or additive action was observed in all strains by combination of MEPM and VCM or TEIC. A combination of MEPM and LZD or ABK showed synergistic or additive 196 strains (94.7%) and 159 strains (76.8%). Antagonism was not observed in any combination of MEPM and VCM, TEIC, or LZD, but 22 strains (10.6%) exhibited antagonism in combination with MEPM and ABK. It is thus important to know both the susceptibility of anti-MRSA agents alone and the combined effects of agents.