Laboratoire de Microbiologie Appliquée à l'Agroalimentaire, au Biomédical et à l'Environnement (LAMAABE), Université de Tlemcen, Tlemcen, Algeria.
Department of Health Sciences, Microbiology Division, University of Jaén, 23071 Jaén, Spain.
J Glob Antimicrob Resist. 2019 Sep;18:291-297. doi: 10.1016/j.jgar.2019.04.005. Epub 2019 Apr 18.
In this study, 77 Enterobacter spp. isolates from a collection of 175 Gram-negative bacilli isolated from Tlemcen University Hospital Center (North-West of Algeria) were tested for antibiotic resistance, biocide tolerance and genetic determinants of antimicrobial resistance.
The isolates were identified by 16S rDNA gene sequencing. Biocide tolerance was determined by broth microdilution, and antibiotic resistance was determined by disk diffusion. Genetic determinants of resistance were studied by PCR amplification using suitable primers.
The most common Enterobacter species was Enterobacter cloacae (58.4%), followed by Enterobacter hormaechei (24.7%). The most common antibiotic resistance was to ticarcillin either alone or in combination with clavulanic acid (70.1%), followed by cefepime (68.8%), cefotaxime (63.6%), ceftazidime (54.5%) and gentamicin (54.5%). Tobramycin was active against 87.0% of the isolates. Levels of biocide tolerance were high for hexachlorophene and to a lesser extent for benzalkonium chloride. The extended-spectrum β-lactamase genes bla and bla were detected in 44.2% and 36.4% of isolates, respectively. Other antimicrobial resistance genes (ARGs) frequently detected were aac(6')-Ib (57.1%) and sul2 (50.6%). Multidrug-resistant isolates carrying several ARGs were common. Significant positive correlations were detected for efflux pump genes with ARGs and also between ARGs.
The results of this study reveal thatEnterobacter spp. isolates from hospital settings are both resistant to clinically-used antibiotics and tolerant to biocides. Biocide tolerance could be an advantage for antibiotic-resistant strains in hospitals.
在这项研究中，从阿尔及利亚西北部泰莱姆森大学医院中心分离的 175 株革兰氏阴性杆菌中分离出的 77 株肠杆菌属分离株进行了抗生素耐药性、杀生物剂耐受性和抗菌药物耐药性的遗传决定因素检测。
通过 16S rDNA 基因测序对分离株进行鉴定。采用肉汤微量稀释法测定杀生物剂耐受性，采用纸片扩散法测定抗生素耐药性。使用合适的引物通过 PCR 扩增研究耐药基因。
最常见的肠杆菌属是阴沟肠杆菌（58.4%），其次是霍氏肠杆菌（24.7%）。最常见的抗生素耐药性是替卡西林，无论是单独使用还是与克拉维酸联合使用（70.1%），其次是头孢吡肟（68.8%）、头孢噻肟（63.6%）、头孢他啶（54.5%）和庆大霉素（54.5%）。妥布霉素对 87.0%的分离株有效。六氯酚和苯扎氯铵的杀生物剂耐受性水平较高。在 44.2%和 36.4%的分离株中分别检测到扩展谱β-内酰胺酶基因 bla 和 bla。经常检测到其他抗菌药物耐药基因（ARGs）是 aac(6')-Ib（57.1%）和 sul2（50.6%）。携带多个 ARGs 的多药耐药分离株很常见。在 ARGs 之间以及在 ARGs 和外排泵基因之间检测到显著的正相关。
本研究结果表明，医院环境中的肠杆菌属分离株对临床使用的抗生素具有耐药性，并对杀生物剂具有耐受性。杀生物剂耐受性可能是医院中抗生素耐药菌株的优势。
