Prevalence of the plasmid-mediated quinolone resistance determinant qnrS among ciprofloxacin-resistant Escherichia coli genotypes in Greece

Abstract number: P1535

Vasilaki O., Ntokou E., Ikonomidis A., Neou E., Nikolaidis P., Alexiou-Daniel S., Maniatis A., Pournaras S.

Objectives: To determine the prevalence of the plasmid-mediated quinolone resistance qnr genes in resistant ciprofloxacin among Escherichia coli clinical isolates.

Methods: During the period 2005 to 2007, 114 ciprofloxacin-resistant Escherichia coli clinical isolates were collected from separate patients (the majority originated from urine cultures) hospitalised in four distant Greek hospitals. Isolates were screened for the presence of genes qnrA, qnrB and qnrS by PCR, using universal primers for each gene amplifying all related alleles. The qnrS-positive isolates were also screened by PCR for the detection of mutations in genes gyrA and parC. DNA-relatedness of the isolates of the study was examined by PFGE. Transferability potency of gene qnrS was investigated by conjugation.

Results: A total 12 out of the 114 tested isolates were positive for the qnrS1 gene but none for qnrA or qnrB gene. The 12 qnrS positive isolates were clonally unrelated and comprised at least 11 out of the 20 detected genotypes. Quinolone resistance was transferable with relatively low frequencies.

Conclusions: This is the first report of qnrS-positive E. coli in Greece. The proportion of approx. 10.5% of quinolone-resistant E. coli that carried qnr genes was considerably high in comparison with respective percentages from others regions, which ranged from 0.5 to 7.7%. All isolates belonged to unrelated clones, indicating that the spread of gene qnrS was not due to clonal dissemination.

Session Details

Date: 19/04/2008
Time: 00:00-00:00
Session name: 18th European Congress of Clinical Microbiology and Infectious Diseases
Location: Barcelona, Spain
Presentation type:
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