Study on the In Vitro Antibacterial Activity of Amoxicillin/tazobactam Against Clinically Isolated 128 Strains of Bacteria / 中国药房

ABSTRACT

OBJECTIVE:Using in vitro studies,we evaluated the antibacterial activity of amoxicillin/tazobactam against 128 strains of pathogens isolated from patients and compared with amoxicillin/clavulanic acid and amoxicillin/sulbactam.METHODS:To detect the minimum inhibitory concentrations (MIC)of four ?-lactams against 128 clinically isolated strains with agar dilution method.RESULTS:The results indicated that the in vitro antibacterial activity of amoxicillin/tazobactam(2∶1) was the best.The MIC50 of amoxicillin/tazobactam(2∶1) is 1/4～1/8 times than those of amoxicillin/sulbutam and amoxicillin/clavulanic acid.The MIC90 of amoxicillin/tazobactam(2∶1) was 1/2～1/4 of those of amoxicillin/sulbutam and amoxicillin/clavulanic acid.The combination ratio 2∶1(amoxicillin/tazobactam)of the two compounds was more suitable than other combination ratios(4∶1 and 8∶1)for inactivating ?-lactamase.CONCLUSION:The in vitro antibacterial activities of amoxicillin/tazobactam(2∶1) against MRSA,MRSE,MSSA and E.coli are high.It showed that amoxicillin/tazobactam(2∶1)is stable to ?-lactamase and is an effective bactericidal agent.