Virulence factors, antibiotic susceptibility and sequence type distribution of hospital-associated Clostridioides difficile isolates in Israel, 2020-2022

Sci Rep. 2024 Sep 4;14(1):20607. doi: 10.1038/s41598-024-71492-2.

Abstract

Biofilm formation and toxin production are some of the virulence factors of Clostridioides difficile (C. difficile), which causes hospital-acquired C. difficile infection (HA-CDI). This work investigated the prevalence and distribution of different strains recovered from HA-CDI patients hospitalized in 4 medical centres across Israel, and characterized strains' virulence factors and antibiotic susceptibility. One-hundred and eighty-eight faecal samples were collected. C. difficile 's toxins were detected by the CerTest Clostridium difficile GDH + Toxin A + B combo card test kit. Toxin loci PaLoc and PaCdt were detected by whole-genome sequencing (WGS). Multi-locus sequence typing (MLST) was performed to classify strains. Biofilm production was assessed by crystal violet. Antibiotic susceptibility was determined using Etest. Fidaxomicin susceptibility was tested via agar dilution. Sequence type (ST) 42 was the most (13.8%) common strain. All strains harboured the 2 toxins genes; 6.9% had the binary toxin. Most isolates were susceptible to metronidazole (98.9%) and vancomycin (99.5%). Eleven (5.85%) isolates were fidaxomicin-resistant. Biofilm production capacity was associated with ST (p < 0.001). In conclusion, a broad variety of C. difficile strains circulate in Israel's medical centres. Further studies are needed to explore the differences and their contribution to HA-CDI epidemiology.

Keywords: Antibiotic susceptibility; Biofilm formation; Hospital-acquired C. difficile infection; Toxin production; Whole-genome sequencing (WGS).

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Bacterial Agents* / pharmacology
  • Biofilms* / drug effects
  • Biofilms* / growth & development
  • Clostridioides difficile* / drug effects
  • Clostridioides difficile* / genetics
  • Clostridioides difficile* / isolation & purification
  • Clostridioides difficile* / pathogenicity
  • Clostridium Infections* / epidemiology
  • Clostridium Infections* / microbiology
  • Cross Infection* / epidemiology
  • Cross Infection* / microbiology
  • Feces / microbiology
  • Female
  • Humans
  • Israel / epidemiology
  • Male
  • Microbial Sensitivity Tests*
  • Middle Aged
  • Multilocus Sequence Typing
  • Virulence Factors* / genetics
  • Whole Genome Sequencing

Substances

  • Anti-Bacterial Agents
  • Virulence Factors