Characterization of Integrons and Quinolone Resistance in Clinical Isolates in Mansoura City, Egypt.

is a common pathogen in both humans and animals. Quinolones are used to treat infections caused by Gram-negative bacteria, but resistance genes emerged. Only scarce studies investigated the association between plasmid-mediated quinolone resistance (PMQR) genes and integrons in clinical isolates of . The current study investigated the prevalence of quinolone resistance and integrons among 134 clinical isolates. Eighty (59.70%) isolates were quinolone-resistant, and 60/134 (44.77%) isolates were integron positive with the predominance of class I integrons (98.33%). There was a significant association between quinolone resistance and the presence of integrons ( < 0.0001). Isolates from Urology and Nephrology Center and Gastroenterology Hospital were significantly quinolone-resistant and integron positive ( ≤ 0.0005). Detection of PMQR genes on plasmids of integron-positive isolates showed that the active efflux pump genes and had the highest prevalence (72.22%), followed by the aminoglycoside acetyltransferase gene (, 66.67%) and the quinolone resistance genes (, 61.11%). Amplification and sequencing of integrons' variable regions illustrated that no quinolone resistance genes were detected, and the most predominant gene cassettes were for trimethoprim and aminoglycoside resistance including , and . In conclusion, this study reported the high prevalence of PMQR genes and integrons among clinical isolates. Although PMQR genes are not cassette-born, they were associated with integrons' presence, which contributes to the widespread of quinolone resistance in Egypt.