tailieunhanh - The first determination of the plasmid-mediated Quinolone resistance determinants qnrA and qnrB from the Sudan

The aim of this study was to determine the prevalence of plasmid-mediated quinolone resistance qnr genes (A, B and S) among a collection of enterobacterial clinical pathogens resistant to ciprofloxacin and was ESBL producers from Sudan. Seventy-two isolates that were ciprofloxacin resistant and ESBL producer were screened by PCR for qnr genes (A, B and S). qnrA positive isolates were tested by PCR for class-1 integrons as well as resistance transfer by conjugation with sodium azide-resistant Escherichia coli J53. DNArelatedness was tested by PFGE. Qnr genes were detected among 13% of the test isolates, seven isolates were qnrB1 positive, included an E. coli and six Klebsiella pneumoniae isolates. qnrA was detected among two Enterobacter cloacae isolates. Genomic analysis by PFGE on the two qnrA positive isolates revealed two closely related organisms. Plasmid transfer of quinolone resistance was achieved on the two qnrA positive isolates, both plasmids showed part of the 3′-CS with the aminoglycoside-3′-adenyltransferases aadA2 and aacA4 genes as well as part of the Intl1 gene which was In6-like class-1 integrons. This study demonstrated high prevalence of qnrB (10%) among the test isolates compared to qnrA (3%) and non of the qnr S. This is the first report on plasmid-mediated ciprofloxacin resistance genes (qnrgenes) from Sudan. | The first determination of the plasmid-mediated Quinolone resistance determinants qnrA and qnrB from the Sudan