Study on in vitro Antibacterial Activity of Cefperazone/Tazobactam

OBJECTIVE: The antibacterial activity in vitro of cefperazone/tazobactam was evaluated. METHODS: Cefperazone/tazobactam (4:1) against 601 clinical isolated strains was compared with cefperazone, tazobactam, cefperazone/sulbactam, piperacillinltazobactam and impipenenilceilastatin. Minimal inhibitory concentrations (MIC) were measured by agar dilution method and minimal bactericidal concentrations (MBC) were measured by broth dilution method. RESULTS: The antibacterial activity of cefperazone/tazobactam (4:1), the MIC50 and MIC90 against the strains producing extended spectrum b-lactamases (ESBLs) were 32-64 times and 16-32 times lower than cefperazone and were 2 times and 4 times lower than cefperazone/sulbactam and piperacillin/tazobactam. The bactericidal activity of cefperazone/tazobactam is better than cefperazone and similar as cefperazone/ sulbactam (1:1) and piperacillin/tazobactam (8:1). The inoculum size, pH and concentration of serum protein did not influence the in vitro the activity of cefperazone/tazobatam (4:1). CONCLUSION: Cefperazone/tazobactam (4:1) is an effective antibiotic containing β-lactamases inhibitor and valuable to be investigated.