title: Multicenter evaluation of the antimicrobial activity for six broad-spectrum beta-lactams in Venezuela: comparison of data from 1997 and 1998 using the Etest method. Venezuelan Antimicrobial Resistance Study Group.
abstract: The minimum inhibitory concentrations of six broad-spectrum beta-lactam antimicrobial agents were determined in 1998 by use of the Etest versus a total of 502 bacteria in seven Venezuelan hospital laboratories. These data were compared with results of a similar study performed in 1997. The organisms tested included 309 recent clinical isolates of Enterobacteriaceae, 70 Pseudomonas aeruginosa, 54 Acinetobacter species, and 69 oxacillin-susceptible Staphylococcus aureus. Extended spectrum beta-lactamase production was noted among 30% of Klebsiella pneumoniae isolates. Hyperproduction of Amp C cephalosporinase producing resistance to ceftazidime and cefotaxime was observed with 10 to 37% of isolates of Enterobacter spp., Serratia spp., and Citrobacter freundii. The overall rank order of activity of the six beta-lactams tested in this study against all clinical isolates was imipenem (96.6% susceptible) > cefepime (90.4%) > piperacillin/tazobactam (85.7%) > ceftazidime (73.5%) > cefotaxime (70.5%) > piperacillin (55.0%). These findings were very similar to those reported for 1997.
authors.affiliation: Department of Pathology, University of Iowa College of Medicine, Iowa City 52242, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Pfaller
authors.forename: R N
authors.initials: RN
authors.lastname: Jones
authors.forename: G V
authors.initials: GV
authors.lastname: Doern
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D002510:Cephalosporinase / Q000096:biosynthesis; D004352:Drug Resistance, Microbial; D004755:Enterobacteriaceae / Q000187:drug effects; D013210:Staphylococcus / Q000187:drug effects; D013997:Time Factors; D014687:Venezuela; D047090:beta-Lactams
chemical_list: D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D002510:Cephalosporinase