摘要

泛耐药肺炎克雷伯氏菌菌株的出现受到越来越多的关注。在本研究中，我们描述了在阿拉伯联合酋长国（阿拉伯联合酋长国）的3家医院中接近4年内遇到的9个耐泛燃肺炎克雷伯氏菌序列147型（ST147）分离株的集群。该菌株表现出高度相似的基因型。全部产生染色体编码的OXA-181，并且大部分也产生NDM-5碳青霉烯酶。与之前描述的来自阿拉伯联合酋长国MS6671的单一分离株一样，mgrB被功能性ISEcp1驱动的blaOXA-181插入导致碳青霉烯耐药性破坏。该突变成功地补充了完整的mgrB基因，表明它是造成粘菌素抗性的原因。 blaNDM-5位于携带ermB，mph（A），blaTEM-1B，rmtB，blaNDM-5，sul1，aadA2和dfrA12抗性基因的约100-kb IncFII质粒的抗性岛内。测序该质粒（pABC143-NDM）显示其主链几乎与质粒pMS6671E相同，几种抗性基因（包括blaNDM-5）已经从该质粒中删除。来自韩国的两株肺炎克雷伯菌ST147分离株的pABC143C-NDM和携带blaNDM-5的IncFII质粒之间发现了更广泛的骨架和抗性岛的相似性，其中一种是粘菌素抗性的，并且都产生了OXA-181 。值得注意的是，这些菌株之一是从阿联酋转移的患者中分离出来的。我们的数据显示，这种抗泛素克隆具有令人震惊的能力，可以长时间维持自身，甚至可能在国际间传播。

The emergence of pan-resistant Klebsiella pneumoniae strains is an increasing concern. In the present study, we describe a cluster of 9 pan-resistant K. pneumoniae sequence type 147 (ST147) isolates encountered in 4 patients over nearly 1 year in 3 hospitals of the United Arab Emirates (UAE). The isolates exhibited highly similar genotypes. All produced chromosomally encoded OXA-181, and the majority also produced the NDM-5 carbapenemase. As with the previously described single isolate from the UAE, MS6671, the mgrB was disrupted by a functional, ISEcp1-driven blaOXA-181 insertion causing resistance to carbapenems. The mutation was successfully complemented with an intact mgrBgene, indicating that it was responsible for colistin resistance. blaNDM-5 was located within a resistance island of an approximately 100-kb IncFII plasmid carrying ermB, mph(A), blaTEM-1B, rmtB, blaNDM-5, sul1, aadA2, and dfrA12resistance genes. Sequencing this plasmid (pABC143-NDM) revealed that its backbone was nearly identical to that of plasmid pMS6671E from which several resistance genes, including blaNDM-5, had been deleted. More extensive similarities of the backbone and the resistance island were found between pABC143C-NDM and the blaNDM-5-carrying IncFII plasmids of two K. pneumoniaeST147 isolates from South Korea, one of which was colistin resistant, and both also produced OXA-181. Notably, one of these strains was isolated from a patient transferred from the UAE. Our data show that this pan-resistant clone has an alarming capacity to maintain itself over an extended period of time and is even likely to be transmitted internationally.

http://aac.asm.org/content/61/7/e00418-17.short