Tomaschek Franziska, Higgins Paul G, Stefanik Danuta, Wisplinghoff Hilmar, Seifert Harald
Institute for Medical Microbiology, Immunology and Hygiene, University of Cologne, Cologne, Germany.
German Centre for Infection Research (DZIF), partner site Cologne-Bonn, Cologne, Germany.
PLoS One. 2016 Apr 12;11(4):e0153014. doi: 10.1371/journal.pone.0153014. eCollection 2016.
To compare the two Acinetobacter baumannii multi-locus sequence typing (MLST) schemes and to assess their suitability to aid in outbreak analysis we investigated the molecular epidemiology of 99 Acinetobacter baumannii isolates representing outbreak-related and sporadic isolates from 24 hospitals in four different countries (Germany, Poland, Sweden, and Turkey). Pulsed-field gel electrophoresis (PFGE) was used as the reference method to determine the epidemiologic relatedness of isolates and compared to MLST using both the Oxford and Pasteur scheme. Rep-PCR was used to define international clonal lineages (IC). We identified 26 unique outbreak strains and 21 sporadic strains. The majority of outbreaks were associated with carbapenem-resistant A. baumannii harbouring oxacillinase OXA-23-like and corresponding to IC 2. Sequence types (STs) obtained from the Oxford scheme correlate well with PFGE patterns, while the STs of the Pasteur scheme are more in accordance with rep-PCR grouping, but neither one is mirroring completely the results of the comparator. On two occasions the Oxford scheme identified two different STs within a single outbreak where PFGE patterns had only one band difference. The CCs of both MLST schemes were able to define clonal clusters that were concordant with the ICs determined by rep-PCR. IC4 corresponds to the previously described CC15 Pasteur (= CC103 Oxford). It can be concluded that both MLST schemes are valuable tools for population-based studies. In addition, the higher discriminatory power of the Oxford scheme that compares with the resolution obtained with PFGE can often aid in outbreak analysis.
为比较两种鲍曼不动杆菌多位点序列分型（MLST）方案，并评估其在暴发分析中的适用性，我们调查了99株鲍曼不动杆菌分离株的分子流行病学情况，这些分离株代表了来自四个不同国家（德国、波兰、瑞典和土耳其）24家医院的与暴发相关及散发的菌株。脉冲场凝胶电泳（PFGE）用作确定分离株流行病学相关性的参考方法，并与使用牛津方案和巴斯德方案的MLST进行比较。重复聚合酶链反应（Rep-PCR）用于定义国际克隆谱系（IC）。我们鉴定出26株独特的暴发菌株和21株散发菌株。大多数暴发与携带类奥沙西林酶OXA-23的耐碳青霉烯鲍曼不动杆菌相关，且对应于IC 2。从牛津方案获得的序列类型（ST）与PFGE模式相关性良好，而巴斯德方案的ST更符合Rep-PCR分组，但两者均未完全反映比较方法的结果。在两次暴发中，牛津方案在单一暴发中鉴定出两种不同的ST，而PFGE模式仅有一条带的差异。两种MLST方案的克隆复合体（CC）均能够定义与通过Rep-PCR确定的IC一致的克隆簇。IC4对应于先前描述的巴斯德CC15（=牛津CC103）。可以得出结论，两种MLST方案都是基于人群研究的有价值工具。此外，与PFGE获得的分辨率相比，牛津方案具有更高的鉴别力，这通常有助于暴发分析。
