Zenati Fatima, Barguigua Abouddihaj, Nayme Kaotar, Benbelaïd Fethi, Khadir Abdelmounaïm, Bellahsene Chafika, Bendahou Mourad, Hafida Hassaïne, Timinouni Mohammed
Laboratory of Applied Microbiology in Food, Biomedical and Environment, Aboubekr Belkaïd University, Tlemcen, Algeria.
Laboratory of Biotechnology and Sustainable Development of Natural Resources, Polydisciplinary Faculty, Sultan Moulay Slimane University, Beni Mellal, Morocco.
J Infect Dev Ctries. 2019 Apr 30;13(4):291-302. doi: 10.3855/jidc.10702.
The aim of this study is to assess the prevalence and molecular characterization of uropathogenic Extended spectrum β-lactamases (ESBLs) producing Escherichia coli.
During 3 years, all hospitalized patients at the University-affiliated hospital of Tlemcen and presenting urinary tract infections caused by E. coli were considered as potential study participants. These E. coli isolates were examined phenotypically for ESBL production. ESBL strains were subjected to antimicrobial susceptibility testing and were investigated for the presence of plasmid mediated quinolone resistance genes, 16SrRNA methylase genes and virulence genes by using conventional PCR and DNA sequencing. The molecular characterization of ESBL strains was established by phylogenetic grouping method and ERIC-PCR.
The overall prevalence of ESBL was 32.5%. The blaCTX-M-15 was the most frequently detected in ESBL isolates, followed by blaCTX-M-14, blaCTX-M-28, blaCTX-M-1 and blaSHV-12 respectively. The plasmid-mediated quinolone resistance genes were detected in the 15 ESBL strains with the aac(6')-Ib-cr gene was the most detected followed by qnrB1 and qnrA1 gene respectively. Among the 22 ESBL isolates resistant to gentamicin and amikacin, the 16SrRNA methylase genes were detected in 4 isolates. The sfa and pap virulent genes were founds in 26% and 22% of isolates receptively. The genotyping analysis of all strains revealed that almost were belonged to phylogenetic groups A1 and A0 and fourteen distinct clones.
The emergence of uropathogenic ESBL isolates and the high rate of blaCTX-M are alarming in Algeria. Strict measure must be required to control the further spread of these strains in Algerian hospitals.
本研究旨在评估产超广谱β-内酰胺酶（ESBLs）的致病性大肠杆菌的流行情况及其分子特征。
在3年期间，所有在特莱姆森大学附属医院住院且由大肠杆菌引起尿路感染的患者被视为潜在研究对象。对这些大肠杆菌分离株进行ESBL产生的表型检测。对ESBL菌株进行抗菌药敏试验，并通过常规PCR和DNA测序检测质粒介导的喹诺酮耐药基因、16SrRNA甲基化酶基因和毒力基因的存在情况。通过系统发育分组法和ERIC-PCR对ESBL菌株进行分子特征分析。
ESBL的总体流行率为32.5%。在ESBL分离株中，blaCTX-M-15是最常检测到的，其次分别是blaCTX-M-14、blaCTX-M-28、blaCTX-M-1和blaSHV-12。在15株ESBL菌株中检测到质粒介导的喹诺酮耐药基因，其中aac(6')-Ib-cr基因检测最多，其次分别是qnrB1和qnrA1基因。在对庆大霉素和阿米卡星耐药的22株ESBL分离株中，4株检测到16SrRNA甲基化酶基因。sfa和pap毒力基因分别在26%和22%的分离株中被发现。对所有菌株的基因分型分析表明，几乎都属于系统发育组A1和A0以及14个不同的克隆。
在阿尔及利亚，致病性ESBL分离株的出现以及blaCTX-M的高发生率令人担忧。必须采取严格措施控制这些菌株在阿尔及利亚医院的进一步传播。
