Plasmid-mediated quinolone resistance genes (PMQR) are mainly associated with clinical isolates of Enterobacteriaceae and complicate treatment of infections caused by these isolates worldwide. Extended-spectrum-beta-lactamase (ESBL)-producing bacteria are resistant to common antibiotics and also through many mechanisms, ESBL could be disabling other types of antibiotics. This study aimed to assess the prevalence of quinolone resistance and ESBL among Enterobacteriaceae strains and investigated the presence of qnrA and qnrB genes in these strains which were isolated from urinary tract infections in Ismailia, Egypt. Ninety-four Enterobacteriaceae isolates were collected from cases of UTIs admitted to the intensive care unit, Suez-Canal University Hospitals, between October 2017 and January 2018. Antibacterial susceptibility was determined by the disk diffusion method. A polymerase chain reaction assay was used to detect qnrA and qnrB resistance genes in quinolone- and fluoroquinolone-resistant and ESBL strains. Also, ciprofloxacin MIC was determined by the agar dilution method. Resistance rates were 59.6%, 54.3%, 53.2%, 53.2%, and 53.2% to NA, LEV, NOR, CIP, and FX, respectively. Of 56 NA-resistant isolates, 7 (12.5%) and 6 (10.7%) were positive for qnrA and qnrB, respectively, with only one isolate co-harboring both genes. ESBL-producing bacteria was 66.2% of isolates. The MICs for ciprofloxacin ranged from 32–256 μg/ml in ciprofloxacin-resistant isolates. Our study shows high resistance rates of Enterobacteriaceae to quinolones and ESBL in our hospital which necessitate appropriate use of these antibiotics to reserve their application for therapy. The prevalence of quinolone-resistant and ESBL-producing Enterobacteriaceae was approximately 60% and 70% respectively.

中文翻译：

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肠杆菌科菌株中质粒介导的 qnrA 和 qnrB 基因的表征：埃及伊斯梅利亚的喹诺酮抗性和 ESBL 生产

质粒介导的喹诺酮抗性基因 (PMQR) 主要与肠杆菌科的临床分离株相关，并使全球这些分离株引起的感染的治疗复杂化。产生超广谱 β-内酰胺酶 (ESBL) 的细菌对常见抗生素具有抗药性，并且通过多种机制，ESBL 可能会禁用其他类型的抗生素。本研究旨在评估肠杆菌科菌株中喹诺酮类耐药性和 ESBL 的流行情况，并调查了这些菌株中 qnrA 和 qnrB 基因的存在，这些菌株是从埃及伊斯梅利亚的尿路感染中分离出来的。从 2017 年 10 月至 2018 年 1 月期间入住苏伊士运河大学医院重症监护室的 UTI 病例收集了 94 株肠杆菌科细菌。抗菌敏感性通过圆盘扩散法测定。聚合酶链反应检测用于检测喹诺酮和氟喹诺酮耐药以及 ESBL 菌株中的 qnrA 和 qnrB 耐药基因。此外，环丙沙星 MIC 通过琼脂稀释法测定。NA、LEV、NOR、CIP 和 FX 的耐药率分别为 59.6%、54.3%、53.2%、53.2% 和 53.2%。在 56 个 NA 抗性分离株中，7 个 (12.5%) 和 6 个 (10.7%) 分别为 qnrA 和 qnrB 阳性，只有一个分离株同时携带这两种基因。产生 ESBL 的细菌占分离株的 66.2%。在环丙沙星耐药分离株中，环丙沙星的 MIC 范围为 32–256 μg/ml。我们的研究表明，我们医院的肠杆菌科细菌对喹诺酮类和 ESBL 的耐药率很高，需要适当使用这些抗生素以保留其治疗应用。喹诺酮类耐药肠杆菌和产 ESBL 肠杆菌的患病率分别约为 60% 和 70%。