Virulence and Genomic Profiles of Klebsiella pneumoniae Isolated from Pediatric Patients in Henan, China (2021–2023)

Abstract

Objective

This study aimed to investigate the virulence characteristics of Klebsiella pneumoniae (KP) strains isolated from children to analyze the genetic relatedness between pediatric and local adult CRKP isolates and to identify clinical risk factors associated with high-risk strains.

Methods

KP strains and corresponding clinical data were collected at a tertiary provincial children's hospital in Henan province from January 2021 to May 2023. The molecular and clinical characteristics of pediatric carbapenem-resistant KP (CRKP) strains were analyzed. Genomic data from local adult isolates were integrated, and the virulence profiles of pediatric and adult isolates were compared. Clinical risk factors for isolating high-risk strains were initially screened via LASSO regression and then evaluated via multivariate binomial regression.

Results

Among the 205 collected KP isolates, 87 (42.4%) were CRKP, and 118 (57.6%) were carbapenem-sensitive KP (CSKP). The predominant carbapenem resistance gene was bla_KPC-2 (89.7%), followed by bla_NDM-1 (5.7%) and bla_IMP-4 (4.6%). Ten sequence types (STs) were identified among the CRKP isolates, with ST11–KL47–KPC2 (52.9%) being the predominant genotype. Screening for virulence genes revealed that 55 (63.2%) CRKP isolates carried both the hypervirulence-associated genes iuc and rmpA2. Single-nucleotide polymorphism (SNP) analysis revealed that 34 of these strains had fewer than 10 SNPs. Phylogenetic and population genetic analyses revealed close genomic relatedness between pediatric and adult CRKP strains. Young age and exposure to invasive procedures were identified as independent risk factors for the isolation of iuc⁺rmpA2⁺ CRKP.

Conclusions

The ST11–KL47–KPC2 genotype was the predominant CRKP isolate in pediatric patients. The close genomic relatedness between pediatric and adult CRKP isolates suggests a common ancestor that has disseminated across populations. The high prevalence and clonal transmission of pediatric iuc⁺rmpA2⁺ CRKP strains warrant heightened clinical vigilance.

Keywords

Carbapenem-resistant Klebsiella pneumoniae / Hypervirulent genes / Children / Virulence / Genomic epidemiology

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