Plasmid-mediated quinolone resistance determinants qnr and aac(6')-Ib-cr in Escherichia coli and Klebsiella spp. from Norway and Sweden.
The prevalence of the plasmid-mediated quinolone resistance genes qnr and aac(6')-Ib-cr was investigated among clinical isolates of Escherichia coli and Klebsiella spp. selected from 2 collections of consecutive isolates collected in 2004 to 2005 in Norway (n = 2479) and Sweden (n = 2980) and 1 group of extended-spectrum beta-lactamase (ESBL)-producing isolates collected in 2003 in Norway (n = 71). A total of 414 isolates was selected for screening based on resistance to nalidixic acid and/or reduced susceptibility/resistance to ciprofloxacin. The prevalence of both qnr and aac(6')-Ib-cr was higher among the ESBL producers (9.1% and 52.3%, respectively) than in the consecutive isolates (1.1% and 3.2%, respectively). qnrS1 was detected in 6 isolates, whereas qnrB1 and qnrB7 were detected in 2 isolates. The genetic structure surrounding qnrS1 was similar to previously described structures. In 2 isolates, qnrS1 was located on conjugative IncN-type plasmids of approximately 140 kb.
Karah
Nabil
N
Reference Centre for Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, 9038 Tromsø, Norway.
Poirel
Laurent
L
Bengtsson
Stina
S
Sundqvist
Martin
M
Kahlmeter
Gunnar
G
Nordmann
Patrice
P
Sundsfjord
Arnfinn
A
Samuelsen
Ørjan
Ø
D000123:Acetyltransferases / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D002876:Chromosomes, Bacterial; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology; D029968:Escherichia coli Proteins / Q000235:genetics*; D023061:Gene Order; D005798:Genes, Bacterial; D006801:Humans; D007709:Klebsiella / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D009664:Norway / Q000453:epidemiology; D010957:Plasmids; D015995:Prevalence; D015363:Quinolones / Q000494:pharmacology*; D013548:Sweden / Q000453:epidemiology
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C485384:Qnr protein, E coli; C485385:Qnr protein, Klebsiella pneumoniae; D015363:Quinolones; D000123:Acetyltransferases; C056532:aminoglycoside N(6')-acetyltransferase