Dataset Information

Prevalence of Carbapenem-Resistant Hypervirulent Klebsiella pneumoniae and Hypervirulent Carbapenem-Resistant Klebsiella pneumoniae in China Determined via Mouse Lethality Tests.

ABSTRACT:

Objective

To investigate the epidemiology of carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-HvKP) and hypervirulent carbapenem-resistant Klebsiella pneumoniae (Hv-CRKP).

Methods

Totally 436 K. pneumoniae strains were collected from 7 hospitals in mainland China between 2017.01 and 2018.02. Sequence types, serotypes, antimicrobial-resistance and virulence genes were analyzed. Additionally, string test, capsule stain, Periodic Acid Schiff stain, fitness analysis, quantitative real-time PCR and mouse lethality test were also performed. Molecular combinations were used to screen putative bla _KPC(+)-HvKP and Hv-bla _KPC(+)-KP, followed by the confirmation of mouse lethality test.

Results

Diverse detection rates were found for the virulence genes, ranging from c-rmpA (0.0%) to entB (100.0%). According to the molecular criteria, 127, 186, 9 and 26 strains were putatively denoted as HvKP, bla _KPC(+)-KP, bla _KPC(+)-HvKP and Hv-bla _KPC(+)-KP. Mouse lethality test confirmed 2 bla _KPC(+)-HvKP strains (JS184 and TZ20) and no Hv-bla _KPC(+)-KP. JS184 showed K2 serotype, thin capsule, positive exopolysaccharid and string test. TZ20 presented K20 serotype, thin capsule, negative exopolysaccharide and string test. Compared with the positive control NTUH-K2044, equal galF expression and growth curves were confirmed for JS184 and TZ20.

Conclusions

Molecular determination of CR-HvKP and Hv-CRKP brings remarkable bias compared with mouse lethality test. The exact prevalence of CR-HvKP is less than 1.0%, which of Hv-CRKP is much lower.

SUBMITTER: Hu D

PROVIDER: S-EPMC9199425 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Publications

Prevalence of Carbapenem-Resistant Hypervirulent <i>Klebsiella pneumoniae</i> and Hypervirulent Carbapenem-Resistant <i>Klebsiella pneumoniae</i> in China Determined <i>via</i> Mouse Lethality Tests.

Hu Dakang D Chen Wenjie W Zhang Qi Q Li Meng M Yang Zehua Z Wang Yong Y Huang Yunkun Y Li Gang G Tian Dongxing D Fu Pan P Wang Weiwen W Ren Ping P Mu Qing Q Yu Lianhua L Jiang Xiaofei X

Frontiers in cellular and infection microbiology 20220601

<h4>Objective</h4>To investigate the epidemiology of carbapenem-resistant hypervirulent <i>Klebsiella pneumoniae</i> (CR-HvKP) and hypervirulent carbapenem-resistant <i>Klebsiella pneumoniae</i> (Hv-CRKP).<h4>Methods</h4>Totally 436 <i>K. pneumoniae</i> strains were collected from 7 hospitals in mainland China between 2017.01 and 2018.02. Sequence types, serotypes, antimicrobial-resistance and virulence genes were analyzed. Additionally, string test, capsule stain, Periodic Acid Schiff stain, fi ...[more]

PMID: 35719357

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