Xiong Liuxin, Su Lebin, Tan Hanqing, Zhao Wansha, Li Shuying, Zhu Yingmei, Lu Limiao, Huang Zhiwei, Li Baisheng
Clinical Laboratory, The Second People's Hospital of Zhaoqing, Zhaoqing, China.
Microbiological Laboratory, Zhaoqing Center for Disease Control and Prevention, Zhaoqing, China.
Front Microbiol. 2021 Sep 27;12:709356. doi: 10.3389/fmicb.2021.709356. eCollection 2021.
(Kp) is the primary causative bacteria for nosocomial infections and hospital outbreaks. In particular, extensively drug-resistant (XDRKp) causes severe clinical infections in hospitalized patients. Here, we used pulsed-field gel electrophoresis (PFGE), drug susceptibility tests, and the whole-genome sequencing (WGS) technology to examine genetic relatedness and phenotypic traits of the strains isolated during an outbreak period. Based on PFGE, a distinct clones cluster comprised of eight XDRKp was observed. These strains were confirmed as ST11-K64 multiple-locus sequence typing database of Kp. The strains also had genes related to the regulation of biofilm biosynthesis (type 1 & 3 fimbriae, type IV pili biosynthesis, , and type VI secretion system) and multiple drug resistance (β-lactamase and aminoglycoside antibiotic resistance). WGS data based on core-single nucleotide polymorphisms and epidemiological investigation showed that the neurosurgery unit was likely the source of the outbreak, the strain was likely to have been transmitted to the ICU through patients. In addition, the two highly probable transmission routes were in the ICU (exposure through shared hospital beds) and the neurosurgery units (all cases were treated by the same rehabilitation physician and were most likely infected during the physical therapy). Notably, the bed mattress had played a crucial transmission role of this outbreak, served as a pathogen reservoir.
肺炎克雷伯菌（Kp）是医院感染和医院内暴发的主要致病菌。特别是广泛耐药的肺炎克雷伯菌（XDRKp）会在住院患者中引发严重的临床感染。在此，我们使用脉冲场凝胶电泳（PFGE）、药敏试验和全基因组测序（WGS）技术来检测暴发期间分离出的菌株的遗传相关性和表型特征。基于PFGE，观察到一个由8株XDRKp组成的独特克隆簇。这些菌株在肺炎克雷伯菌多位点序列分型数据库中被确认为ST11-K64。这些菌株还具有与生物膜生物合成调控相关的基因（1型和3型菌毛、IV型菌毛生物合成以及VI型分泌系统）和多重耐药性（β-内酰胺酶和氨基糖苷类抗生素耐药性）。基于核心单核苷酸多态性的WGS数据和流行病学调查表明，神经外科病房可能是此次暴发的源头，该菌株可能通过患者传播到了重症监护病房（ICU）。此外，两条极有可能的传播途径分别在ICU（通过共用病床接触）和神经外科病房（所有病例均由同一位康复医生治疗，最有可能在物理治疗期间感染）。值得注意的是，床垫在此次暴发中起到了关键的传播作用，充当了病原体储存库。
