With increasing antibiotic resistance in gram-negative pathogens, dosing strategies that optimize pharmacodynamic parameters of currently available antibiotics play an important role in treatment. The likelihood of success with piperacillin/tazobactam, a widely used broad-spectrum antibiotic, can be manipulated by increasing the amount of time that unbound drug concentrations remain above the p...

We compared ceftazidime-avibactam, ceftolozane-tazobactam, ceftazidime, cefepime, and piperacillin-tazobactam MICs for 38 meropenem-resistant Pseudomonas aeruginosa isolates. No isolates harbored carbapenemases; 74% were oprD mutants. Ceftazidime-avibactam and ceftolozane-tazobactam were active against 92% of the isolates, including 80% that were resistant to all three β-lactams. Forty-three pe...

BACKGROUND The extensive use of the β-lactam antibiotics in hospitals and in the community has created major resistance problems which has led to increased morbidity, mortality and healthcare costs. The use of the β-lactamase inhibitors in combination with the β-lactam antibiotics is currently the most successful strategy used for circumventing the resistance mechanisms. OBJECTIVE To evaluate...

Mecillinam was tested in vitro alone or in combination with piperacillin-tazobactam and azithromycin against representative species of the Enterobacteriaceae family and Pseudomonas aeruginosa to extend its antibacterial spectrum, and to protect mecillinam from inactivating enzymes taking advantage of the presence of tazobactam. Drug interactions were studied by microdilution method, by selectio...

BACKGROUND Periodic monitoring of regional or institutional resistance trends of clinically important anaerobic bacteria is recommended, because the resistance of anaerobic pathogens to antimicrobial drugs and inappropriate therapy are associated with poor clinical outcomes. There has been no multicenter study of clinical anaerobic isolates in Korea. We aimed to determine the antimicrobial resi...

Sir, We report here a study that was undertaken to investigate whether ciprofloxacin resistance in Gram-negative noso-comial pathogens is a surrogate marker for cross-resistance to non-fluoroquinolones. The organisms, Escherichia coli (n = 3315), Pseudomonas aeruginosa (n = 1370), Entero-bacter aerogenes (n = 252), Enterobacter cloacae (n = 495), Proteus mirabilis (n = 379), Serratia marcescens...

Characterization of impurities present in generic antimicrobial agents is not required according to the approval criteria for their sale worldwide. To assess the safety of generics, we conducted a structural estimation of impurities in six piperacillin/tazobactam generics and carried out an in silico analysis. Namely, these generics were compared with the brand name drug by HPLC and LC-MS. The ...

Two-hundred consecutive, single patient isolates of Enterobacter spp., Serratia spp., Citrobacter spp., and Pseudomonas aeruginosa were evaluated for AmpC production using a variety of inducer-substrate antibiotic combinations in a disk approximation format. The combinations examined included cefoxitin-piperacillin, imipenem-cefotaxime, imipenem-ceftazidime, imipenem-piperacillin-tazobactam, an...

MICs of eight beta-lactams (piperacillin, piperacillin-tazobactam, ticarcillin, ticarcillin-clavulanate, ampicillin, ampicillin-sulbactam, ceftazidime, and ceftriaxone) were determined by agar dilution against 64 penicillin-susceptible, 70 intermediately penicillin-resistant, and 66 fully penicillin-resistant pneumococci. The MICs of piperacillin with and without tazobactam for 90% of the susce...