Clinical and molecular characteristics of KPC-producing Klebsiella pneumoniae bloodstream infections: Results of a multicentre study

J Glob Antimicrob Resist. 2025 Mar:41:216-223. doi: 10.1016/j.jgar.2025.01.009. Epub 2025 Jan 24.

Abstract

Objective: Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-Kp) is a great cause of concern and often associated with bloodstream infections (BSIs) and a high mortality rate. Here we identified the risk factors of KPC-Kp BSIs observed in three Italian hospitals and studied the epidemiology of KPC-Kp strains.

Methods: A retrospective analysis of KPC-Kp BSIs was performed from 2014 to 2019 at three hospitals in central Italy (Ancona, Pesaro-Fano, and Perugia). Uni- and multi-variable analyses were performed to evaluate the clinical variables associated with mortality. Pulsed-field gel electrophoresis assay and whole-genome sequencing analysis of KPC-Kp isolates was carried out to identify antibiotic resistance genes and epidemiological relationships among the strains.

Results: A total of 219 patients were considered. Mortality on day 30 was 32%, with older age, APACHE II score ≥11, Charlson Comorbidity Index ≥4, and solid tumours more frequent in patients with a negative outcome. Positive outcomes were related to combination therapy with at least two active drugs that also emerged in multivariate analysis. Most KPC-Kp strains belonged to three major sequence types (ST512, ST307, and ST101), while the most common carbapenem resistance gene variant was blaKPC-3.

Conclusions: KPC-Kp BSIs remain a challenging infection with a high crude mortality rate. Patient conditions and comorbidities correlate with negative outcomes, while active drugs are correlated with better outcomes. Although collected from different hospitals, the KPC-Kp strains were epidemiologically related, suggesting inter-hospital diffusion. Timely and effective therapy, together with epidemiological surveillance, are crucial to reduce mortality and prevent the spread of nosocomial clones.

Keywords: Bloodstream infections; Carbapenemases; KPC; Klebsiella pneumoniae.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Bacteremia* / epidemiology
  • Bacteremia* / microbiology
  • Bacteremia* / mortality
  • Bacterial Proteins* / genetics
  • Bacterial Proteins* / metabolism
  • Drug Resistance, Multiple, Bacterial / genetics
  • Electrophoresis, Gel, Pulsed-Field
  • Female
  • Humans
  • Italy / epidemiology
  • Klebsiella Infections* / drug therapy
  • Klebsiella Infections* / epidemiology
  • Klebsiella Infections* / microbiology
  • Klebsiella Infections* / mortality
  • Klebsiella pneumoniae* / drug effects
  • Klebsiella pneumoniae* / enzymology
  • Klebsiella pneumoniae* / genetics
  • Klebsiella pneumoniae* / isolation & purification
  • Male
  • Microbial Sensitivity Tests
  • Middle Aged
  • Retrospective Studies
  • Risk Factors
  • Whole Genome Sequencing
  • beta-Lactamases* / genetics
  • beta-Lactamases* / metabolism

Substances

  • beta-Lactamases
  • Bacterial Proteins
  • carbapenemase
  • Anti-Bacterial Agents