Doumith M, Findlay J, Hirani H, Hopkins K L, Livermore D M, Dodgson A, Woodford N
Antimicrobial Resistance and Healthcare Associated Infections (AMRHAI) Reference Unit, National Infection Service, Public Health England, London NW9?5EQ, UK.
Antimicrobial Resistance and Healthcare Associated Infections (AMRHAI) Reference Unit, National Infection Service, Public Health England, London NW9 5EQ, UK.
J Antimicrob Chemother. 2017 Aug 1;72(8):2241-2248. doi: 10.1093/jac/dkx141.
Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae were first seen in the UK in 2003 and have been increasingly reported since 2010, largely owing to an ongoing outbreak in North-West England. We examined the role of clonal spread and plasmid transmission in their emergence.
Isolates comprised KPC-positive K. pneumoniae ( n = 33), Escherichia coli ( n = 7) and Enterobacter spp. ( n = 4) referred to the national reference laboratory between 2008 and 2010 from 17 UK centres, including three in North-West England. Isolates were typed by MLST. Plasmids were transferred by electroporation and characterized by PCR or sequencing. PCR screening assays were developed to distinguish plasmid pKpQIL variants.
The K. pneumoniae isolates included 10 STs, of which three belonged to clonal group (CG) 258. CG258 ( n = 19) isolates were detected in 13 centres but accounted for only 7/19 (36.8%) of those from North-West England. Most KPC-producers (37/44, 84.1%), including 16/19 CG258 K. pneumoniae , carried bla KPC on IncFII K2 plasmids. Sequencing of a subset of these plasmids ( n = 11) revealed similarities with published pKpQIL. One variant, pKpQIL-UK [identified in K. pneumoniae CG258 ( n = 5) and ST468 ( n = 1) isolates from distinct centres] had only a few nucleotide changes from classical pKpQIL, whereas pKpQIL-D1 ( n = 1) and pKpQIL-D2 ( n = 4), from isolates of various species in the North-West, harboured large variations, reflecting replacement of the partitioning and replication functions and potentially thereby facilitating spread. PCR revealed that 36/37 (97.3%) IncFII K2 -type plasmids in KPC-positive isolates had pKpQIL markers.
pKpQIL-like plasmids played a major role in the early dissemination of KPC enzymes in the UK.
产肺炎克雷伯菌碳青霉烯酶（KPC）的肠杆菌科细菌于2003年首次在英国被发现，自2010年以来报告数量不断增加，这主要归因于英格兰西北部持续存在的疫情暴发。我们研究了克隆传播和质粒传递在其出现过程中的作用。
分离株包括2008年至2010年间从英国17个中心（包括英格兰西北部的3个中心）送至国家参考实验室的KPC阳性肺炎克雷伯菌（n = 33）、大肠埃希菌（n = 7）和肠杆菌属细菌（n = 4）。分离株通过多位点序列分型（MLST）进行分型。质粒通过电穿孔进行转移，并通过PCR或测序进行鉴定。开发了PCR筛查试验以区分质粒pKpQIL变体。
肺炎克雷伯菌分离株包括10个序列型（ST），其中3个属于克隆群（CG）258。在13个中心检测到了CG258（n = 19）分离株，但仅占来自英格兰西北部分离株的7/19（36.8%）。大多数产KPC的菌株（37/44，84.1%），包括16/19的CG258肺炎克雷伯菌，在IncFII K2质粒上携带blaKPC。对这些质粒的一个子集（n = 11）进行测序后发现与已发表的pKpQIL有相似性。一种变体pKpQIL-UK[在来自不同中心的肺炎克雷伯菌CG258（n = 5）和ST468（n = 1）分离株中鉴定到]与经典pKpQIL相比只有少数核苷酸变化，而来自西北部不同物种分离株的pKpQIL-D1（n = 1）和pKpQIL-D2（n = 4）存在较大变异，这反映了分配和复制功能的替换，可能因此促进了传播。PCR显示，KPC阳性分离株中36/37（97.3%）的IncFII K2型质粒具有pKpQIL标记。
pKpQIL样质粒在英国KPC酶的早期传播中起主要作用。
