高毒力肺炎克雷伯菌研究进展

Research progress on hypervirulent Klebsiella pneumoniae

近年来,高毒力肺炎克雷伯菌成为备受关注的病原体。与普通肺炎克雷伯菌常导致免疫力低下人群的院内感染不同,高毒力肺炎克雷伯菌常引起健康个体的社区感染,且极易发生远处部位的转移,最常见的转移部位包括眼、肺和中枢神经系统,感染常需从源头控制。高毒力肺炎克雷伯菌的毒力基因通常位于大毒力质粒和染色体上的可移动遗传元件上,可作为生物标记与普通肺炎克雷伯菌临床分离株进行区分。高毒力肺炎克雷伯菌的相关毒力因素包括4个铁载体系统促进铁摄取、荚膜产量增加、K1和K2荚膜血清型及colibactin毒素。值得注意的是,耐多药的高毒性菌株已经出现,并日益增多,给临床诊疗带来了新的挑战。为更好地了解高毒力肺炎克雷伯菌,文章对其特性、流行病学特征、毒力相关因素及耐药性进行介绍。

Recently,hypervirulent Klebsiella pneumoniae has emerged as a concerning pathogen.In contrast to nosocomial infections in immuno-compromised patients with classic Klebsiella pneumoniae,hypervirulent Klebsiella pneumoniae usually causes community acquired infections in healthy individuals and is prone to metastasize to distant sites,including most commonly the eye,lung and central nervous system,and often requiring source control.The genetic determinants of hypervirulent Klebsiella pneumoniae are often found on large virulence plasmids as well as chromosomal mobile genetic elements which can be used as biomarkers to distinguish hypervirulent Klebsiella pneumoniae from common Klebsiella pneumoniae clinical isolates.These distinct virulence determinants of hypervirulent Klebsiella pneumoniae include up to 4 siderophore systems for iron acquisition,increased capsule production,K1 and K2 capsule types and colibactin toxin.Alarmingly,multidrug-resistant hypervirulent isolates have emerged,creating a new challenge in combating this already dangerous pathogen.In order to better understand hypervirulent Klebsiella pneumoniae,the characteristics,epidemiology,virulence related factors and drug resistance with hypervirulent Klebsiella pneumoniae will be introduced in detail.