Statens Serum Institut, Copenhagen S, Denmark
Statens Serum Institut, Copenhagen S, Denmark.
J Antimicrob Chemother. 2015 Jul;70(7):1965-8. doi: 10.1093/jac/dkv072. Epub 2015 Mar 19.
The objectives were to study a possible outbreak of carbapenem-resistant Acinetobacter baumannii by comparing three different typing methods (PFGE, MLST and whole-genome SNPs) and to compare the resistance gene profiles of the isolates.
From December 2012 to October 2013, eight carbapenem-resistant A. baumannii were detected at Odense University Hospital, Odense, Denmark. These isolates were typed by PFGE, with ApaI and SmaI, respectively, and subjected to WGS. The WGS data were used for in silico extraction of MLST types using two different schemes, resistance genes and SNPs, to which 31 publicly available A. baumannii genomes were added.
Using ApaI, the eight isolates had four different PFGE profiles, which were further differentiated using SmaI, separating one of the profiles into two distinct PFGE types. Five ST2 (Pasteur MLST) OXA-23-producing isolates, two ST1 OXA-72-producing isolates and one ST158 OXA-23-producing isolate were detected. The five ST2 isolates were subdivided into ST195, ST208 and ST218 using the Oxford MLST scheme. The phylogenetic analysis based on the core genome showed that six of the eight Danish A. baumannii isolates were located in three distinct clusters. The two remaining isolates did not cluster with other Danish or international isolates included in the study. Isolates that clustered using PFGE, Oxford MLST and phylogenetic analysis also shared similar resistance gene profiles.
The SNP profile, Oxford MLST, PFGE and resistance gene profiles clearly indicated spread of three different A. baumannii strains.
通过比较三种不同的分型方法（PFGE、MLST 和全基因组 SNPs），研究碳青霉烯类耐药鲍曼不动杆菌的可能暴发，并比较分离株的耐药基因谱。
2012 年 12 月至 2013 年 10 月，丹麦欧登塞大学医院检测到 8 株碳青霉烯类耐药鲍曼不动杆菌。这些分离株分别用 ApaI 和 SmaI 进行 PFGE 分型，并进行 WGS。使用 WGS 数据通过两种不同的方案（MLST 型、耐药基因和 SNPs）进行 MLST 型的计算机提取，并添加了 31 个公开的鲍曼不动杆菌基因组。
使用 ApaI，这 8 个分离株有 4 种不同的 PFGE 图谱，进一步用 SmaI 分离，将其中一种图谱分为两种不同的 PFGE 类型。检测到 5 株携带 OXA-23 的 ST2（巴斯德 MLST）、2 株携带 OXA-72 的 ST1、1 株携带 OXA-23 的 ST158 分离株。使用牛津 MLST 方案，这 5 株 ST2 分离株进一步细分为 ST195、ST208 和 ST218。基于核心基因组的系统发育分析表明，这 8 株丹麦鲍曼不动杆菌分离株中的 6 株位于 3 个不同的簇中。其余 2 株与本研究中包括的其他丹麦或国际分离株没有聚类。聚类的 PFGE、牛津 MLST 和系统发育分析也具有相似的耐药基因谱。
SNP 谱、牛津 MLST、PFGE 和耐药基因谱清楚地表明了三种不同鲍曼不动杆菌菌株的传播。
