title: [In vitro activity of tazobactam and piperacillin combination against 224 strains of Pseudomonas aeruginosa according to the production of beta-lactamase].
abstract: Piperacillin (PIP) alone and combined with 4 mg/l, 8 mg/l of tazobactam (TAZ) were tested by MIC determination on Mueller-Hinton agar against 224 clinical strains of P. aeruginosa: "wild type" (BLA-), 32 producing a constitutive cephalosporinase (CEP), 41 producing the PSE-1 type beta-lactamase, 7 PSE-2, 8 PSE-3, 9 PSE-4, 13 TEM-1, 24 TEM-2, 13 OXA-1, 22 OXA-2, 5 OXA-3. The combination with 8 mg/l was more effective than that one with 4 mg/l. Combinations of PIP-TAZ 8 mg/l reduced the MICs of PIP for the resistant strains (MICs greater than 64 mg/l) to the susceptible ot the moderately susceptible range (MICs less than or equal to 64 mg/l) for 31% of the CEP producing strains, 63% of the PSE-1, 15% of the PSE-2, none of the PSE-3, 34% of the PSE-4, 39% of the TEM-1, 30% of the TEM-2, 23% of the OXA-1, 14% of the OXA-2, 27% of the OXA-3, TAZ is the first beta-lactamase inhibitor effective against the constitutive cephalosporinase of P. aeruginosa; it is also very effective against the most frequently found PSE-1 beta-lactamase in P. aeruginosa.
authors.affiliation: Laboratoire de Biologie Médicale, Hôpital d'Instruction des Armées Bégin, Saint-Mandé.
authors.forename: A
authors.initials: A
authors.lastname: Thabaut
authors.forename: M
authors.initials: M
authors.lastname: Meyran
mesh_terms: D002510:Cephalosporinase / Q000032:analysis; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D004352:Drug Resistance, Microbial; D004357:Drug Synergism; D066298:In Vitro Techniques; D010397:Penicillanic Acid / Q000494:pharmacology*; D010878:Piperacillin / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000201:enzymology; D000078142:Tazobactam; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000032:analysis*
chemical_list: D004338:Drug Combinations; D065093:beta-Lactamase Inhibitors; D010397:Penicillanic Acid; D002510:Cephalosporinase; D001618:beta-Lactamases; D000078142:Tazobactam; D010878:Piperacillin
vernacular_title: Activité in vitro de l'association pipéracilline-tazobactam sur 224 souches de Pseudomonas aeruginosa en fonction de la production de bêtalactamase.