Is intestinal colonization with multidrug-resistant Enterobacterales associated with higher rates of nosocomial Enterobacterales bloodstream infections?

Int J Infect Dis. 2025 Jan:150:107274. doi: 10.1016/j.ijid.2024.107274. Epub 2024 Nov 5.

Abstract

Objectives: Intestinal colonization with multidrug-resistant Enterobacterales (MDRE-IC) increases the risk of MDRE bloodstream infection (BSI). However, its impact on the overall risk of nosocomial Enterobacterales bloodstream infections (nE-BSIs) remains unclear. This study aimed to determine this risk and identify associated factors in hospitalized patients.

Design: This retrospective cohort study at a 3200-bed tertiary institution including patients hospitalized in 2019 who underwent MDRE rectal swab (RS) screening. Inclusion criteria were age ≥18 years, first RS in 2019, follow-up ≥7 days, and Enterobacterales BSIs >48 hours after RS. The primary outcome was the first nE-BSI during the follow-up period, analyzed using a Cox model.

Results: Among 7006 patients, 817 (11.9%) had MDRE-IC. Most were male and primarily hospitalized in acute wards. nE-BSIs occurred in 433 (6.1%) patients and were more frequent in patients with MDRE-IC than the non-colonized group (adjusted hazard ratio [aHR] = 1.78, 95% confidence interval [CI]: 1.40-2.26). Intestinal colonization with extended-spectrum β-lactamase-producing and carbapenemase-resistant Enterobacterales showed similar risks for Enterobacterales BSI onset: aHR = 1.73 (95% CI: 1.33-2.24) and aHR = 2.02 (95% CI: 1.27-3.22), respectively.

Conclusions: In hospitalized patients, MDRE-IC is associated with a higher rate of nE-BSI than those without MDRE-IC, underscoring the urgent need for improved infection prevention and control measures, as well as optimized antibiotic use to mitigate this risk.

Keywords: Antibiotic resistance; Bloodstream infection; Carbapenemase-resistant Enterobacterales; Extended-spectrum β-lactamases; Intestinal colonization; Nosocomial infection.

MeSH terms

  • Adult
  • Aged
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Bacteremia* / epidemiology
  • Bacteremia* / microbiology
  • Cross Infection* / epidemiology
  • Cross Infection* / microbiology
  • Drug Resistance, Multiple, Bacterial*
  • Enterobacteriaceae Infections* / epidemiology
  • Enterobacteriaceae Infections* / microbiology
  • Enterobacteriaceae* / drug effects
  • Enterobacteriaceae* / isolation & purification
  • Female
  • Humans
  • Male
  • Middle Aged
  • Rectum / microbiology
  • Retrospective Studies
  • Risk Factors

Substances

  • Anti-Bacterial Agents