title: Multidrug resistance among Enterobacteriaceae is strongly associated with the presence of integrons and is independent of species or isolate origin.
abstract: This study investigated the extent to which multidrug resistance (MDR) among Enterobacteriaceae is related to DNA elements called "integrons," whether the relationship is species dependent or origin dependent, and which resistance patterns are associated with integrons. Analysis of 867 nonrepeat isolates comprising 8 species and originating from the community and 23 European hospitals showed a significant relation between MDR and integrons, independent of species or origin. Although resistance to each tested antimicrobial agent was significantly associated with integrons, only resistance to sulfamethoxazole, cotrimoxazole, gentamicin, tobramycin, ampicillin, piperacillin, and cefuroxime predicted the presence of integrons. Combined resistance to both ampicillin and sulfamethoxazole-trimethoprim was the starting point for the development of resistance to additional beta-lactams, aminoglycosides, cephalosporins, and ciprofloxacin, a development paralleled by an increasing prevalence of integrons. The acquisition of resistance genes is not random, and the transfer of integron-carrying elements plays a dominant role in the development of MDR by Enterobacteriaceae.
authors.affiliation: Eijkman-Winkler Institute for Microbiology, Infectious Diseases and Inflammation, University Medical Centre, Utrecht, The Netherlands. M.LeversteinvHall@lab.azu.nl
authors.forename: Maurine A
authors.initials: MA
authors.lastname: Leverstein-van Hall
authors.forename: Hetty E
authors.initials: HE
authors.lastname: M  Blok
authors.forename: A Rogier
authors.initials: AR
authors.lastname: T  Donders
authors.forename: Armand
authors.initials: A
authors.lastname: Paauw
authors.forename: Ad C
authors.initials: AC
authors.lastname: Fluit
authors.forename: Jan
authors.initials: J
authors.lastname: Verhoef
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D004755:Enterobacteriaceae / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D032023:Integrons / Q000235:genetics*; D010641:Phenotype; D016133:Polymerase Chain Reaction; D013045:Species Specificity
chemical_list: D000900:Anti-Bacterial Agents