title: [In vitro synergistic activity of piperacillin-tazobactam combination against beta-lactam antibiotics resistant strains of Enterobacteriaceae].
abstract: The combination of piperacillin and tazobactam was studied in a microtiter checkerboard assay against 160 strains of Enterobacteriaceae selected for their resistance pattern to amoxicillin, ticarcillin, cephalothin and cefotaxime. Mean FIC indices were respectively 0.02, 0.17 and 0.01 for RRSS strains of E. coli, K. pneumoniae and P. mirabilis. Mean FIC indices were 0.03 for RRRI/R strains of K. pneumoniae producing a broad spectrum beta-lactamase, but the synergistic effect was out of therapeutic range for 16 strains of 20. Mean FIC indices were 0.53, 0.90, 0.55, 0.10 and 0.21 respectively against RSRS strains of E. coli, E. cloacae, S. marcescens, M. morganii and P. vulgaris. Mean FIC indices were 0.02, 0.07, 0.02 and 0.01 against RRRS/R strains of E. coli, E. cloacae, S. marcescens and M. morganii but they were in a therapeutical range (piperacillin less than or equal to 8 mg/l and tazobactam less than or equal to 4 mg/l) respectively for 7, 0, 4 and 10 strains of 10 in each species. Tazobactam restored the antibacterial activity of piperacillin against enterobacterial strains mainly producing a penicillinase or a cephalosporinase for M. morganii and P. vulgaris.
authors.affiliation: Laboratoire de Bactériologie-Hygiène, Centre Hospitalier, Universitaire de Dijon, Hôpital du Bocage.
authors.forename: J M
authors.initials: JM
authors.lastname: Duex
authors.forename: X
authors.initials: X
authors.lastname: Cordin
authors.forename: A
authors.initials: A
authors.lastname: Péchinot
authors.forename: E
authors.initials: E
authors.lastname: Siebor
authors.forename: A
authors.initials: A
authors.lastname: Kazmierczak
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D004352:Drug Resistance, Microbial; D004357:Drug Synergism; D004755:Enterobacteriaceae / Q000187:drug effects*; D066298:In Vitro Techniques; D010397:Penicillanic Acid / Q000494:pharmacology*; D010878:Piperacillin / Q000494:pharmacology*; D000078142:Tazobactam; D065093:beta-Lactamase Inhibitors
chemical_list: D000900:Anti-Bacterial Agents; D004338:Drug Combinations; D065093:beta-Lactamase Inhibitors; D010397:Penicillanic Acid; D000078142:Tazobactam; D010878:Piperacillin
vernacular_title: Activité synergique in vitro de l'association pipéracilline-tazobactam vis-à-vis d'entérobactéries résistantes aux bêtalactamines.