高毒力肺炎克雷伯菌致病及耐药分子机制研究进展

Research progress in the mechanism of molecular pathogenesis and drug resistance of hypervirulent Klebsiella pneumoniae

近年来,肺炎克雷伯菌已成为医院内感染及社区获得性感染的常见致病菌,临床标本分离率仅次于大肠埃希菌。根据毒力特征差异,肺炎克雷伯菌可分为经典肺炎克雷伯菌和高毒力肺炎克雷伯菌2种类型。高毒力肺炎克雷伯菌是引起化脓性肝脓肿的主要病原菌,其感染可出现内源性转移,包括眼、肺和中枢神经系统;此外还与原发性肝外感染有关,包括菌血症、肺炎和软组织感染。值得关注的是,高毒力肺炎克雷伯菌除了导致患者出现严重感染外,目前已出现了碳青霉烯耐药高毒力株,这将为临床诊疗带来更多的挑战。本文就高毒力肺炎克雷伯菌的流行现状、毒力因子(包括荚膜多糖、铁载体系统以及毒力基因)、耐药现状及其主要机制等方面的研究现状进行综述,以期为以后的深入研究提供参考。

Klebsiella pneumoniae is one of the common pathogens in nosocomial and community-acquired infections. The clinical specimen isolation rate of Klebsiella pneumoniae is only behind the Escherichia coli in Gram-negative bacteria. Klebsiella pneumoniaes are divided into classic Klebsiella pneumoniae and hypervirulent Klebsiella pneumonia according to the differences characteristics in virulence. Hypervirulent Klebsiella pneumoniae is the main pathogen of suppurative liver abscess, and its infection can cause many endogenous metastases, including eye, lung and central nervous systems. Hypervirulent Klebsiella pneumoniae is also associated with primary extrahepatic infections, including bacteremia, pneumonia, and soft tissue infections. It is noteworthy that in addition to causing severe infection in patients, hypervirulent strains resistant to carbapenem have emerged in recent years, which will bring more challenges in clinical diagnosis and treatment. In this paper, the epidemic status, the virulence factors(including capsular, iron carrier system and virulence genes), and the current status of drug resistance of hypervirulent Klebsiella pneumoniae are reviewed.