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Published on: March 2, 2020
Plasmid-mediated quinolone resistance in Australia
Jose-Manuel Rodriguez-Martinez1, Laurent Poirel, Alvaro Pascual
1Service de Bactériologie-Virologie, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Faculté de Médecine Paris-Sud, Université Paris XI, K.-Bicêtre, France.
Microbial Drug Resistance (Larchmont, N.Y.)
|August 23, 2006
Summary
This study found the first plasmid-mediated quinolone resistance in Australian Enterobacteriaceae. The qnrA gene was detected in two ESBL-positive isolates, indicating emerging quinolone resistance.
Area of Science:
- Microbiology
- Molecular Biology
- Antimicrobial Resistance
Background:
- Fluoroquinolone resistance is a growing public health concern.
- Extended-spectrum beta-lactamase (ESBL) production further complicates treatment options.
- Plasmid-mediated resistance determinants are key drivers of antimicrobial resistance spread.
Purpose of the Study:
- To investigate the presence of plasmid-encoded quinolone resistance genes (qnrA and qnrS) in Australian Enterobacteriaceae.
- To characterize the genetic environment of identified resistance determinants.
- To establish the first report of plasmid-mediated quinolone resistance in Enterobacteriaceae in Australia.
Main Methods:
- Polymerase Chain Reaction (PCR) was used to detect qnrA, qnrS, and ESBL genes.
- Isolates were identified as fluoroquinolone-resistant and/or ESBL-producing.
- Genetic analysis of plasmids and resistance gene locations was performed.
Main Results:
- The qnrA gene was identified in two of 23 fluoroquinolone-resistant isolates, both of which were ESBL-positive.
- No qnrS gene was detected.
- The QnrA1 determinant was found in Enterobacter cloacae and Klebsiella pneumoniae isolates, both expressing SHV-12 ESBL.
- K. pneumoniae K149 harbored plasmids with qnrA and bla(SHV)-12, and a carbapenemase gene bla(IMP-4).
- The qnrA gene structure was consistent with previously reported strains from China.
Conclusions:
- This study reports the first identification of plasmid-mediated quinolone resistance (QnrA) in Enterobacteriaceae in Australia.
- The findings highlight the potential for rapid dissemination of quinolone resistance through mobile genetic elements.
- Continued surveillance is crucial to monitor the emergence and spread of antimicrobial resistance.
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