title: Multicenter evaluation of the in vitro activity of six broad-spectrum beta-lactam antimicrobial agents in Puerto Rico. The Puerto Rico Antimicrobial Resistance Study Group.
abstract: The minimum inhibitory concentrations of 6 broad-spectrum beta-lactam antimicrobial agents were determined by use of the Etest versus a total of 569 bacteria in 7 Puerto Rican hospital laboratories. These included 342 recent clinical isolates of Enterobacteriaceae, 63 Pseudomonas aeruginosa, 54 Acinetobacter species, and 110 oxacillin-susceptible staphylococci. Extended spectrum beta-lactamase production was noted among 11% of Klebsiella pneumoniae isolates. Hyperproduction of Amp C cephalosporinase was observed with > 20% of isolates of Enterobacter spp., Serratia spp., and Citrobacter freundii. The overall rank order of activity of the six beta-lactams examined in this study versus all clinical isolates was imipenem (95.8% susceptible) > cefepime (91.1%) > piperacillin/ tazobactam (82.3%) > cefotaxime (77.6%) > piperacillin (72.5%) > ceftazidime (67.0%).
authors.affiliation: Department of Pathology, University of Iowa College of Medicine, Iowa City 52242, USA.
authors.forename: G V
authors.initials: GV
authors.lastname: Doern
authors.forename: R N
authors.initials: RN
authors.lastname: Jones
authors.forename: M A
authors.initials: MA
authors.lastname: Pfaller
authors.forename: M
authors.initials: M
authors.lastname: Erwin
authors.forename: C
authors.initials: C
authors.lastname: Ramirez-Rhonda
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis; D003430:Cross-Sectional Studies; D004352:Drug Resistance, Microbial; D016946:Gram-Negative Aerobic Rods and Cocci / Q000187:drug effects / Q000302:isolation & purification; D006095:Gram-Positive Cocci / Q000187:drug effects / Q000302:isolation & purification; D006801:Humans; D008826:Microbial Sensitivity Tests; D011647:Puerto Rico; D047090:beta-Lactams
chemical_list: D000900:Anti-Bacterial Agents; D047090:beta-Lactams