Tazobactam-piperacillin compared with sulbactam-ampicillin, clavulanic acid-ticarcillin, sulbactam-cefoperazone, and piperacillin for activity against beta-lactamase-producing bacteria isolated from patients with complicated urinary tract infections.

The antibacterial activity of tazobactam-piperacillin was compared with that of sulbactam-ampicillin, clavulanic acid-ticarcillin, sulbactam-cefoperazone and piperacillin against beta-lactamase-producing bacteria isolated from patients with complicated urinary tract infections. Tazobactam-piperacillin showed a broad antibacterial spectrum against gram-negative and gram-positive bacteria. The minimum inhibitory concentrations (MIC90) of tazobactam-piperacillin were 6.25 micrograms/ml against Escherichia coli, 1.56 micrograms/ml against Proteus mirabilis, 3.13 micrograms/ml against Proteus vulgaris, 6.25 micrograms/ml against methicillin-susceptible Staphylococcus aureus, and 6.25 micrograms/ml coagulase-negative methicillin-susceptible staphylococci. Against all beta-lactamase-producing bacteria tested the antibacterial activity of tazobactam-piperacillin was at least 4- to 64-fold stronger than that of piperacillin, clavulanic acid-ticarcillin, and sulbactam-ampicillin, and similar to or greater than that of sulbactam-cefoperazone except for E. coli.