AUTHOR=Wu Xingbing , Shi Qingyi , Shen Shimo , Huang Chen , Wu Hongcheng 

TITLE=Clinical and Bacterial Characteristics of Klebsiella pneumoniae Affecting 30-Day Mortality in Patients With Bloodstream Infection

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=11

YEAR=2021

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2021.688989

DOI=10.3389/fcimb.2021.688989

ISSN=2235-2988

ABSTRACT=<sec><title>Background</title><p>There is a paucity of studies using clinical characteristics and whole-genome sequencing together to fully identify the risk factors of patients with <italic>Klebsiella pneumoniae</italic> (KP) bloodstream infection (BSI).</p></sec><sec><title>Methods</title><p>We retrospectively analyzed the clinical and microbiological characteristics of patients with KP BSI. Isolates were processed using Illumina NGS, and relevant bioinformatics analysis was conducted (multi-locus sequence typing, serotype, phylogenetic reconstruction, detection of antibiotic resistance, and virulence genes). A logistic regression model was used to evaluate the risk factors of hosts and causative KP isolates associated with 30-day mortality in patients infected with KP BSI.</p></sec><sec><title>Results</title><p>Of the 79 eligible patients, the 30-day mortality rate of patients with KP BSI was 30.4%. Multivariate analysis showed that host-associated factors (increased APACHE II score and septic shock) were strongly associated with increased 30-day mortality. For the pathogenic factors, carriage of <italic>iutA</italic> (OR, 1.46; 95% CI, 1.11–1.81, <italic>p</italic> = 0.002) or <italic>Kvar_1549</italic> (OR, 1.31; 95% CI, 1.02–1.69, <italic>p</italic> = 0.043) was an independent risk factor, especially when accompanied by a multidrug-resistant phenotype. In addition, ST11-K64 hypervirulent carbapenem-resistant KP co-harbored acquired <italic>bla<sub>KPC-2</sub></italic> together with <italic>iutA</italic> (76.5%, 13/17) and <italic>Kvar_1549</italic> (100%, 17/17) genes. Comparative genomic analysis showed that they were clustered together based on a phylogenetic tree, and more virulence genes were observed in the group of ST11-K64 strains compared with ST11-non-K64. The patients infected with ST11-K64 strains were associated with relatively high mortality (47.2%, 7/17).</p></sec><sec><title>Conclusion</title><p>The carriage of <italic>iutA</italic> and <italic>Kvar_1549</italic> was seen to be an independent mortality risk factor in patients with KP BSI. The identification of hypervirulent and carbapenem-resistant KP strains associated with high mortality should prompt surveillance.</p></sec>