Prévalence des gènes de résistance plasmidique aux quinolones chez des entérobactéries communautaires isolées au Maroc ( Prevalence of plasmid mediated quinolone resistance genes among enterobacteria isolates in Moroccan community )

Introduction: Quinolones have a powerful antimicrobial activity and are frequently prescribed in general medicine. This study aims to evaluate the emergence of plasmid mediated quinolone resistance «PMQR» genes among enterobacterial isolates from Morocco. Material and methods: 237 enterobacterial strains were isolated from community setting. Resistance to antibiotics and the detection of extended-spectrum β-lactamases (ESBL) were conducted according to the recommendations of the French Society of Microbiology; PMQR, ESBL (TEM, SHV and CTXM) and AmpC genes were screened by PCR. The aac(6')-Ibcr gene was identified by PCR-RFLP. All PCR products were sequenced. Conjugation experiments were done using the sodium azide-resistant strain E. coli K12J5. Results: 26.3% of the strains are resistant to at least 5 antibiotics; 7 strains (3%) show an ESBL phenotype. The prevalence of «PMQR» genes is 11.10%: the qnr gene was found in 6 isolates with a rate of 1.7% for qnrS1 and 0.9% for qnrB (B5, B6). The aac(6')-Ib-cr gene was detected in 8.5% of the strains. The qnrA and qepA genes were not found. Conjugation experiments showed that the genes qnrS1, aac(6')-Ib-cr and CTX-M-15 have been co-transfered together and that these genes are carried on conjugative plasmids of high molecular weight. Conclusion: This study confirms the dissemination of qnr and aac(6')-Ib-cr in Moroccan community setting. However, the high level of antibiotic resistance concerns a high risk of transmission of multidrug-resistant bacteria and challenges the authorities for surveillance of resistance policy.