Over the past decades, Escherichia coli (E. coli) have acquired extensive resistance to antibiotics; especially β- lactams. This study aimed to investigate the frequency of Extended-spectrum β-lactamase (ESBL) and carbapenemase producers among E. coli isolates and their correlation with serotypes, phylogenetic background, and pathogenicity associated islands. A total of 105 E. coli strains were isolated and subjected to antimicrobial susceptibility testing against β-lactam antibiotics. All isolates showed a high resistance profile. Resistant isolates were tested for ESBL and carbapenemase production. Fifty-three and 18 isolates were positive for ESBL and carbapenemase producers, respectively. ESBL and carbapenemase genes were detected by PCR. TEM gene was the most prevalent gene among all isolates followed by SHV and CTX-M15. In carbapenemase-producers, OXA-48 and IMP were the predominant genes. Enteropathogenic E. coli (EPEC) and Enterohemorrhagic E. coli (EHEC) were the major producers of ESBL and carbapenemase, respectively as indicated by serodiagnosis. They were further assessed for the presence of pathogenicity islands (PAIs) and phylogenetic background. The most predominant DEC PAI and ExPEC PAI were HPI and IICFT073. Most clinically ESBL-producers were group D and B2 while environmentally ones were group B1 and A. On contrary, clinically carbapenemase-producers belonged to group C and D. In conclusion, our study confirms the importance of phylogenetic group D, B2, and C origin for antibiotic resistance in E. coli. Ultimately, our findings support the fact that environmental isolates contribute to the local spread of E. coli pathogenicity in Egypt and these isolates maybe serve as reservoirs for transmission of resistance.

中文翻译：

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从埃及医院和环境中分离出的产生超广谱 β-内酰胺酶和碳青霉烯酶的大肠杆菌的遗传特征。


在过去的几十年里，大肠杆菌（E. coli）对抗生素产生了广泛的耐药性；特别是β-内酰胺。本研究旨在调查大肠杆菌分离株中超广谱 β-内酰胺酶 (ESBL) 和碳青霉烯酶产生者的频率及其与血清型、系统发育背景和致病性相关岛的相关性。共分离出 105 株大肠杆菌，并对其进行了针对 β-内酰胺类抗生素的药敏试验。所有分离株均表现出高耐药性。对耐药菌株进行了 ESBL 和碳青霉烯酶生产测试。 53 株和 18 株分离株分别呈 ESBL 和碳青霉烯酶生产阳性。 PCR检测ESBL和碳青霉烯酶基因。 TEM 基因是所有分离株中最常见的基因，其次是 SHV 和 CTX-M15。在碳青霉烯酶产生者中，OXA-48 和 IMP 是主要基因。血清诊断显示，肠致病性大肠杆菌 (EPEC) 和肠出血性大肠杆菌 (EHEC) 分别是 ESBL 和碳青霉烯酶的主要产生者。进一步评估了它们是否存在致病岛（PAI）和系统发育背景。最主要的 DEC PAI 和 ExPEC PAI 是 HPI 和 IICFT073。大多数临床ESBL产生者属于D组和B2组，而环境产生者属于B1组和A组。相反，临床碳青霉烯酶产生者属于C组和D组。总之，我们的研究证实了系统发育组D、B2和C的重要性大肠杆菌抗生素耐药性的起源。最终，我们的研究结果支持这样一个事实：环境分离株有助于大肠杆菌致病性在埃及的局部传播，并且这些分离株可能充当耐药性传播的储存库。