Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China.
Epidemiol Infect. 2020 Mar 12;148:e69. doi: 10.1017/S0950268820000655.
Bloodstream infection (BSI), caused by Klebsiella pneumoniae, is associated with high morbidity and mortality, where the pks gene cluster plays a major role in their occurrence and prevalence. Information on the prevalence and characteristics of this gene cluster in K. pneumoniae is currently limited in mainland China. We therefore undertook a multicentre longitudinal study which revealed the prevalence, overall, community-onset and hospital-acquired BSI to be 20.5%, 28.3% and 13.0%, respectively. Compared to pks-negative, pks-positive isolates were significantly more susceptible to antimicrobial agents with a low incidence (5.1%) of multidrug-resistance and with infrequent extended-spectrum beta-lactamase (ESBL) production. Among pks-positive isolates, ST23 (78/117) and ST65 (20/117) were the dominant sequence types, and the majority harboured virulence genes. Community-onset BSI patients infected with pks-positive isolates had a higher proportion of liver abscesses and a lower proportion of biliary obstructions (P < 0.05). The pks-positive isolates were mostly sporadic in the phylogenetic tree, with a 65.8 and 47.0 average allele difference between Clade 1 and Clade 2, respectively. We concluded that although pks-positive K. pneumoniae were generally susceptible to antimicrobials, the high prevalence of such isolates in community cases and the genotoxicity, merits further investigation.
血流感染（BSI）由肺炎克雷伯菌引起，与高发病率和死亡率相关，其中 pks 基因簇在其发生和流行中起主要作用。目前，中国内地有关肺炎克雷伯菌 pks 基因簇的流行情况和特征的信息有限。因此，我们进行了一项多中心纵向研究，结果显示，该基因簇在总体、社区获得性和医院获得性 BSI 中的流行率分别为 20.5%、28.3%和 13.0%。与 pks 阴性相比，pks 阳性分离株对抗菌药物的敏感性显著更高，耐药发生率（5.1%）较低，且很少产生超广谱β-内酰胺酶（ESBL）。在 pks 阳性分离株中，ST23（78/117）和 ST65（20/117）是主要的序列类型，大多数携带毒力基因。社区获得性 BSI 患者感染 pks 阳性分离株时，肝脓肿的比例较高，胆道梗阻的比例较低（P<0.05）。pks 阳性分离株在系统发育树上主要呈散在分布，与 clade1 和 clade2 相比，平均等位基因差异分别为 65.8 和 47.0。综上所述，虽然 pks 阳性肺炎克雷伯菌通常对抗菌药物敏感，但此类分离株在社区病例中的高流行率以及其遗传毒性值得进一步研究。
