title: High rates of resistance to piperacillin/tazobactam among Escherichia coli and Klebsiella pneumoniae strains isolated in a Greek hospital.
abstract: The activities of piperacillin/tazobactam (PTZ) and 10 other beta-lactams were evaluated by a broth microdilution method using the PASCO system in 1078 Escherichia coli and 447 Klebsiella pneumoniae strains isolated from hospitalized patients in a Greek hospital. Overall, 10.5% of the former and 62.6% of the latter strains displayed resistance to PTZ. Most of the PTZ-resistant strains (71.2%) expressed extended spectrum beta-lactamases and were also resistant to broad spectrum cephalosporins and aztreonam. The high rates of PTZ resistance in E. coli and K. pneumoniae and the extensive cross-resistance to other beta-lactams suggest that PTZ should be used with caution in our clinical setting.
authors.affiliation: Department of Medical Microbiology, Aristotelian University of Thessaloniki, Greece.
authors.forename: A
authors.initials: A
authors.lastname: Tsakris
authors.forename: J
authors.initials: J
authors.lastname: Douboyas
authors.forename: L S
authors.initials: LS
authors.lastname: Tzouvelekis
mesh_terms: D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects*; D006115:Greece; D006801:Humans; D007711:Klebsiella pneumoniae / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D010397:Penicillanic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology*; D010878:Piperacillin / Q000494:pharmacology*; D000078142:Tazobactam
chemical_list: D004791:Enzyme Inhibitors; D010406:Penicillins; D010397:Penicillanic Acid; D000078142:Tazobactam; D010878:Piperacillin