摘要

多药耐药鲍曼不动杆菌的全球成功与传播指定克隆复合体（CC）92B（Bartual计划）/ CC2P（巴斯德计划）的高危克隆相关，后者是欧洲，亚洲最常见的遗传谱系，和北美碳青霉烯耐药不动杆菌分离株。在这些分离株中，碳青霉烯抗性主要由blaOXA-23样，blaOXA-24样，blaOXA-51样和/或blaOXA-58样基因编码的β-内酰胺酶介导。在这项研究中，我们描述了从哥伦比亚七个城市（2008-2010）的14家医院回收的121株碳青霉烯耐药鲍曼不动杆菌复合分离株的群体遗传学特征。多重PCR用于检测blaOXA-23样，blaOXA-24样，blaOXA-51样和blaOXA-58样基因。使用脉冲场凝胶电泳（PFGE）和多位点序列分型（MLST）进行分子分型。 PCR显示118个（97.5％）的分离物对于blaOXA-23样和blaOXA-51样基因都是阳性的，并且另外三个分离物对于blaOXA-51样阳性。 PFGE鉴定了18种不同的脉冲型，而MLST鉴定出11种不同的序列类型（ST），其中7种以前没有在不动杆菌中描述过。在本研究中发现的STs均未与CC92B / CC2P相关。我们分离株中最广泛的ST属于ST636和它们的单基因座变体ST121 / ST124 / ST634（CC636B），其次是属于CC110B的ST。我们的观察结果表明，在哥伦比亚医院（包括CC636B和CC110B）中广泛分布的含有blaOXA-23样的不同鲍氏不动杆菌复合体克隆与世界其他地区常见的高危克隆不同，表明其具有独特的分子流行病学特征耐碳青霉烯不动杆菌属。

The global success of multidrug-resistant Acinetobacter baumannii has been associated with the dissemination of a high-risk clone designated clonal complex (CC) 92B (Bartual scheme)/CC2P (Pasteur scheme), which is the most frequent genetic lineage in European, Asian, and North American carbapenem-resistant Acinetobacter isolates. In these isolates, carbapenem resistance is mainly mediated by β-lactamases encoded by blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, and/orblaOXA-58-like genes. In this study, we characterized the population genetics of 121 carbapenem-resistant A. baumanniicomplex isolates recovered from 14 hospitals in seven cities in Colombia (2008–2010). Multiplex PCR was used to detectblaOXA-23-like, blaOXA-24-like, blaOXA-51-like, and blaOXA-58-like genes. Molecular typing was performed using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). PCR showed that 118 (97.5%) of the isolates were positive for both blaOXA-23-like and blaOXA-51-like genes, and three other isolates were only positive for blaOXA-51-like. PFGE identified 18 different pulsotypes, while MLST identified 11 different sequence types (STs), seven of which had not been previously described in Acinetobacter. None of the STs found in this study was associated with CC92B/CC2P. The most widespread STs in our isolates belonged to ST636 and their single-locus variants ST121/ST124/ST634 (CC636B) followed by STs belonging to CC110B. Our observations suggest a wide distribution of diverse A. baumannii complex clones containingblaOXA-23-like in Colombian hospitals (especially CC636B and CC110B) that differ from the high-risk clones commonly found in other regions of the world, indicating a distinct molecular epidemiology of carbapenem-resistant Acinetobacter spp. in Colombia.

https://www.liebertpub.com/doi/abs/10.1089/mdr.2016.0190