Enterohemorrhagic E. Coli (EHEC)


  • Enterohemorrhagic E. coli (EHEC)
    • Virulence Factors
      • O157:H7 is most common EHEC serotype in US
      • Produces Shiga-like toxin (verotoxin)
        • inactivates 60s ribosomal subunit, stopping protein production and leading to cell death
        • Major mediator of pathogenicity; toxin-mediated enterocyte death and intestinal hemorrhage
        • Similar to the mechanism of shiga toxin in Shigella spp.
          • Contrast vs. Shigella, where toxin plays minor role in pathogenesis
    • Transmission
      • Ingested via undercooked meat (beef)
        • unpasteurized milk, contaminated water are also sources
    • Presentation
      • Bloody Diarrhea
      • May be complicated by Hemolytic-uremic syndrome (HUS)
        • Triad of hemolytic anemia, thrombocytopenia, and kidney injury