Service de Bactériologie-Virologie, INSERM U914 Emerging Resistance to Antibiotics, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Faculté de Médecine et Université Paris-Sud, K.-Bicêtre, Paris, France.
J Antimicrob Chemother. 2011 Aug;66(8):1730-3. doi: 10.1093/jac/dkr174. Epub 2011 May 31.
To analyse the mechanisms responsible for decreased susceptibility or resistance to carbapenems in several enterobacterial isolates recovered in 2009-10 in Geneva University Hospitals, Switzerland.
PCR and sequencing were used to identify β-lactamases, 16S RNA methylases and plasmid-mediated quinolone resistance genes. The transferable properties of the plasmids were analysed, as well as their plasmid type. The strains were typed by multilocus sequence typing.
Three patients were found to be positive for NDM-1-producing enterobacterial isolates (one with Escherichia coli and Klebsiella pneumoniae, one with K. pneumoniae only and one with Proteus mirabilis), where NDM-1 stands for New Delhi metallo-β-lactamase-1. The bla(NDM-1) carbapenemase gene was detected in all isolates in addition to genes encoding narrow-spectrum β-lactamases (TEM-1, SHV-11, OXA-1, OXA-9 and OXA-10), extended-spectrum β-lactamases (CTX-M-15, CMY-16 and CMY-30), ArmA and quinolone resistance determinants (Qnr). The bla(NDM-1) gene was located on conjugative IncA/C- or IncF-type plasmids. Upstream of the bla(NDM-1) gene, part of ISAba125, previously identified in NDM-1-negative Acinetobacter baumannii, was found. Downstream of the bla(NDM-1) gene, variable sequences were found.
This work constitutes the first identification of NDM-1 producers in Switzerland. Interestingly, patients from whom these NDM-1-producing isolates were recovered had a link with the Indian subcontinent or the Balkans.
分析 2009-10 年期间在瑞士日内瓦大学附属医院分离的几株肠杆菌对碳青霉烯类药物敏感性降低或耐药的机制。
采用 PCR 和测序方法鉴定β-内酰胺酶、16S RNA 甲基化酶和质粒介导的喹诺酮耐药基因。分析质粒的可转移性及其质粒类型。采用多位点序列分型对菌株进行分型。
发现 3 例产 NDM-1 的肠杆菌（1 例为大肠埃希菌和肺炎克雷伯菌，1 例为肺炎克雷伯菌，1 例为奇异变形杆菌），NDM-1 代表新德里金属β-内酰胺酶-1。除编码窄谱β-内酰胺酶（TEM-1、SHV-11、OXA-1、OXA-9 和 OXA-10）、广谱β-内酰胺酶（CTX-M-15、CMY-16 和 CMY-30）、ArmA 和喹诺酮耐药决定子（Qnr）的基因外，所有分离株均检测到 bla(NDM-1) 碳青霉烯酶基因。bla(NDM-1) 基因位于可接合 IncA/C-或 IncF 型质粒上。在 bla(NDM-1) 基因上游，发现了先前在 NDM-1 阴性鲍曼不动杆菌中鉴定出的 ISAba125 的一部分。bla(NDM-1) 基因下游发现了可变序列。
这项工作首次在瑞士发现了 NDM-1 产酶菌。有趣的是，从这些产 NDM-1 分离株中分离出的患者与印度次大陆或巴尔干半岛有关。
