Molecular Characterization of Plasmid-mediated Quinolone Resistance in Gram-negative Bacilli from Semen Samples in Ouagadougou

The widespread use of fluoroquinolones has led to the emergence of resistant strains, complicating the treatment of bacterial infections. This study aimed to analyze quinolone resistance in Gram-negative bacilli isolated from semen samples in Burkina Faso. A total of 311 semen samples were used in the study. The bacteria present were isolated and identified using standard methods. Antibiotic susceptibility was assessed, and isolates resistant to at least one of the quinolones tested were analyzed by conventional PCR to detect the resistance genes aac(6')-Ib, qnrA, qnrB, and qnrS. A total of 8 samples (2.58%) were culture-positive, with a predominance of Escherichia coli (62.5%) and Klebsiella pneumoniae (37.5%). All Klebsiella pneumoniae species were susceptible to antibiotics, while Escherichia coli strains showed resistance rates of 50% to ciprofloxacin, 37.5% to norfloxacin, and 12.5% to levofloxacin. Molecular analysis of the isolates revealed a high prevalence of the qnrA gene (75%), followed by the aac(6')-Ib and qnrB genes (50% each). In addition, 50% of isolates contained both the qnrA and qnrB genes, and 25% contained both aac(6')-Ib and qnrA. The detection of these plasmid resistance genes highlights the importance of monitoring the evolution of antibiotic resistance and promoting the judicious use of antibiotics in order to limit its spread.