title: In vitro evaluation of broad-spectrum beta-lactams in the philippines medical centers: role of fourth-generation cephalosporins. The Philippines Antimicrobial Resistance Study Group.
abstract: Cefepime is a potent broad-spectrum "fourth-generation" cephalosporin. The in vitro activity of cefepime was compared to that of cefpirome, ceftazidime, ceftriaxone, imipenem, and piperacillin/tazobactam in a multilaboratory (nine medical centers) Philippine surveillance project from March through October 1998. A total of 626 Gram-positive and Gram-negative organisms (10 species groups) were tested by the Etest method (AB BIODISK, Solna, Sweden) with results validated by current quality control strain analysis. The overall rank order of usable spectrum of activity was imipenem (4.2% resistance), cefepime (4.5%), cefpirome (5.0%), piperacillin/tazobactam (5.8%) > ceftriaxone (11.2%) > ceftazidime (15.3%), and results did not differ significantly between medical centers. Ceftazidime-resistant Escherichia coli and Klebsiella spp. occurred at rates of 13.3% and 31.1%, respectively, indicating extended-spectrum beta-lactamase (ESBL) activity. Imipenem (100% susceptible), cefepime, and cefpirome (both > or = 97.8% susceptible) were active in vitro against these ESBL phenotypes. Organisms with ceftazidime and/or ceftriaxone-resistant profiles consistent for hyper-production of Amp C cephalosporinases were detected at high rates among the Citrobacter spp. (29.2%) and Enterobacter spp. (45.8%); however, imipenem (100.0% susceptible) and cefepime (98.9%) remained active. Cefepime and imipenem (both 87.5% susceptible) were the most active agents tested against Acinetobacter spp. whereas piperacillin/tazobactam was most effective against P. aeruginosa (80.0% susceptible). Most tested beta-lactams (except ceftazidime) were active versus oxacillin-susceptible staphylococci. These data should be used as a guide for treatment selection with beta-lactam compounds in the Philippines and to serve as a resistance benchmark in comparisons with future studies in this nation.
authors.affiliation: Department of Pathology, University of Iowa College of Medicine, Iowa City 52242, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Johnson
authors.forename: D J
authors.initials: DJ
authors.lastname: Biedenbach
authors.forename: R N
authors.initials: RN
authors.lastname: Jones
mesh_terms: D001419:Bacteria / Q000187:drug effects*; D000077723:Cefepime; D002511:Cephalosporins / Q000494:pharmacology*; D004755:Enterobacteriaceae / Q000187:drug effects; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006801:Humans; D008826:Microbial Sensitivity Tests; D013210:Staphylococcus / Q000187:drug effects
chemical_list: D002511:Cephalosporins; D000077723:Cefepime