Current Research in Microbiology and Biotechnology

Qnr genes are known to confer a low level resistance to fluoroquinolone in Enterobacteriaceae. Their presence with other antibiotic resistance mechanism as extended spectrum β-lactamase (ESBL) on the same plasmid are common and can spread widely. This study aimed to detect the presence of qnr genes in ESBL-producing commensal Enterobacteriaceae in 443 children aged 6 to 59 months included in a clinical trial conducted by Doctors without Borders/Epicentre at Maradi, Niger. A total of 78 strains among 163 ESBL-producing commensal Enterobacteriaceae with phenotypic resistance to quinolone were selected and identified with the API 20E identification system. A multiplex PCR with specific primers was then performed to detect the presence of qnrA, qnrB and qnrS genes. These strains included 63 E. coli and 15 Klebsiella spp. We found 42 (53.9%) of them harboring at least one qnr gene: E. coli (n=28) and Klebsiella spp (n=14) : 4 (9.5%) qnrA, 11 (26.2%) qnrB and 27 (64. 3%) qnrS. This is the first identification of qnr genes in ESBL producing commensal E. coli and Klebsiella spp in children without antibiotic therapy in the seven precedent days in Niger. These genes could be involved in the resistance to quinolones in Niger.