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

Xingbing Wu; Qingyi Shi; Shimo Shen; Chen Huang; Hongcheng Wu

doi:10.3389/fcimb.2021.688989

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

Front Cell Infect Microbiol. 2021 Sep 16:11:688989. doi: 10.3389/fcimb.2021.688989. eCollection 2021.

Authors

Xingbing Wu¹, Qingyi Shi², Shimo Shen³, Chen Huang³, Hongcheng Wu³

Affiliations

¹ Department of Infectious Diseases, Ningbo Medical Center Lihuili Hospital, Ningbo, China.
² Department of Rheumatology, Ningbo Medical Center Lihuili Hospital, Ningbo, China.
³ Department of Respiratory Medicine, Ningbo Medical Center Lihuili Hospital, Ningbo, China.

Abstract

Background: There is a paucity of studies using clinical characteristics and whole-genome sequencing together to fully identify the risk factors of patients with Klebsiella pneumoniae (KP) bloodstream infection (BSI).

Methods: 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.

Results: 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 iutA (OR, 1.46; 95% CI, 1.11-1.81, p = 0.002) or Kvar_1549 (OR, 1.31; 95% CI, 1.02-1.69, p = 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 bla_KPC-2 together with iutA (76.5%, 13/17) and Kvar_1549 (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).

Conclusion: The carriage of iutA and Kvar_1549 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.

Keywords: Klebsiella pneumoniae; bloodstream infection (BSI); carbapenem-resistant; hypervirulent; mortality; risk factors.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Anti-Bacterial Agents / pharmacology
Bacteremia*
Humans
Klebsiella Infections* / epidemiology
Klebsiella pneumoniae / genetics
Multilocus Sequence Typing
Phylogeny
Retrospective Studies

Substances

Anti-Bacterial Agents