title: Molecular surveillance of European quinolone-resistant clinical isolates of Pseudomonas aeruginosa and Acinetobacter spp. using automated ribotyping.
abstract: Nosocomial isolates of Pseudomonas aeruginosa and Acinetobacter spp. exhibit high rates of resistance to antibiotics and are often multidrug resistant. In a previous study (D. Milatovic, A. Fluit, S. Brisse, J. Verhoef, and F. J. Schmitz, Antimicrob. Agents Chemother. 44:1102-1107, 2000), isolates of these species that were resistant to sitafloxacin, a new advanced-generation fluoroquinolone with a high potency and a broad spectrum of antimicrobial activity, were found in high proportion in 23 European hospitals. Here, we investigate the clonal diversity of the 155 P. aeruginosa and 145 Acinetobacter spp. sitafloxacin-resistant isolates from that study by automated ribotyping. Numerous ribogroups (sets of isolates with indistinguishable ribotypes) were found among isolates of P. aeruginosa (n = 34) and Acinetobacter spp. (n = 16), but the majority of the isolates belonged to a limited number of major ribogroups. Sitafloxacin-resistant isolates (MICs > 2 mg/liter, used as a provisional breakpoint) showed increased concomitant resistance to piperacillin, piperacillin-tazobactam, ceftriaxone, ceftazidime, amikacin, gentamicin, and imipenem. The major ribogroups were repeatedly found in isolates from several European hospitals; these isolates showed higher levels of resistance to gentamicin and imipenem, and some of them appeared to correspond to previously described multidrug-resistant international clones of P. aeruginosa (serotype O:12) and Acinetobacter baumannii (clones I and II). Automated ribotyping, when used in combination with more discriminatory typing methods, may be a convenient library typing system for monitoring future epidemiological dynamics of geographically widespread multidrug-resistant bacterial clones.
authors.affiliation: Eijkman-Winkler Institute, Utrecht University, 3584 CX Utrecht, The Netherlands. sbrisse@lab.azu.nl
authors.forename: S
authors.initials: S
authors.lastname: Brisse
authors.forename: D
authors.initials: D
authors.lastname: Milatovic
authors.forename: A C
authors.initials: AC
authors.lastname: Fluit
authors.forename: K
authors.initials: K
authors.lastname: Kusters
authors.forename: A
authors.initials: A
authors.lastname: Toelstra
authors.forename: J
authors.initials: J
authors.lastname: Verhoef
authors.forename: F J
authors.initials: FJ
authors.lastname: Schmitz
mesh_terms: D042462:4-Quinolones; D000150:Acinetobacter / Q000145:classification / Q000187:drug effects / Q000235:genetics*; D000151:Acinetobacter Infections / Q000382:microbiology*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001331:Automation; D003428:Cross Infection / Q000382:microbiology*; D004352:Drug Resistance, Microbial; D005060:Europe; D024841:Fluoroquinolones; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology / Q000379:methods; D010802:Phylogeny; D011552:Pseudomonas Infections / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000145:classification / Q000187:drug effects / Q000235:genetics*; D021521:Ribotyping / Q000379:methods; D013019:South Africa
chemical_list: D042462:4-Quinolones; D000890:Anti-Infective Agents; D024841:Fluoroquinolones; C076246:sitafloxacin