Genetic characterization of Shiga toxin producing Escherichia coli belonging to the emerging hybrid pathotype O80:H2 isolated from humans 2010-2017 in Switzerland

Int J Med Microbiol. 2018 Jul;308(5):534-538. doi: 10.1016/j.ijmm.2018.05.007. Epub 2018 Jun 1.

Abstract

Shiga toxin-producing E. coli (STEC) O80:H2 is an uncommon hybrid pathotype that has recently emerged in France. We analysed 18 STEC O80:H2 isolated from humans in Switzerland during 2010-2017. All isolates carried stx2a or stx2d, the rare eae variant eae-ξ and at least seven virulence genes associated with pS88, a plasmid that is found in extraintestinal pathogenic E. coli (ExPEC). Whole genome sequencing (WGS) identified additional chromosomal extraintestinal virulence genes encoding for type 1 fimbria (fimA, fimC and fimH), aerobactin (iuc/iutA) and afimbrial adhesins (afaA/C/D/E-VIII). Core genome multi-locus sequence typing (cgMLST) detected two closely related but distinct subclusters with different stx2 and iuc/iutA genotypes. All isolates were multidrug resistant (MDR), but susceptible to third generation cephalosporins and azithromycin. STEC/ExPEC hybrid pathotypes such as STEC O80:H2 represent a therapeutical challenge in the event of extraintestinal infection.

Keywords: Core genome; Extraintestinal; Hybrid; STEC O80:H2; Virulence.

MeSH terms

  • Adhesins, Bacterial / genetics*
  • Adhesins, Escherichia coli / genetics
  • Azithromycin / pharmacology
  • Cephalosporins / pharmacology
  • Drug Resistance, Multiple, Bacterial / genetics
  • Escherichia coli Proteins / genetics
  • Extraintestinal Pathogenic Escherichia coli / pathogenicity*
  • Fimbriae Proteins / genetics*
  • Genome, Bacterial / genetics
  • Humans
  • Hydroxamic Acids / metabolism
  • Microbial Sensitivity Tests
  • Multilocus Sequence Typing
  • Plasmids / genetics
  • Shiga Toxin / classification
  • Shiga Toxin / genetics*
  • Shiga-Toxigenic Escherichia coli / drug effects
  • Shiga-Toxigenic Escherichia coli / genetics*
  • Shiga-Toxigenic Escherichia coli / isolation & purification
  • Shiga-Toxigenic Escherichia coli / pathogenicity*
  • Switzerland
  • Virulence Factors / genetics

Substances

  • Adhesins, Bacterial
  • Adhesins, Escherichia coli
  • Cephalosporins
  • Escherichia coli Proteins
  • Hydroxamic Acids
  • Virulence Factors
  • fimC protein, E coli
  • fimH protein, E coli
  • fimbrillin
  • Fimbriae Proteins
  • aerobactin
  • Shiga Toxin
  • Azithromycin