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Verotoxin-producing ''Escherichia coli'' consists of strains of the bacterium ''Escherichia coli'' that, when infecting humans, have been linked with the severe complication hemolytic-uremic syndrome (HUS). They are known by a number of names, including enterohemorrhagic ''E. coli'' (EHEC), shiga-like toxin-producing ''E. coli'' (STEC or SLTEC), hemolytic uremic syndrome–associated enterohaemorrhagic ''E. coli'' (HUSEC) and verocytotoxin- or verotoxin-producing ''E. coli'' (VTEC). All these strains of pathogenic bacteria produce Shiga-like toxin (also known as verotoxin), a major cause of foodborne illness. These are distinguished from other pathotypes of intestinal pathogenic ''E. coli'' including enterotoxigenic ''E. coli'' (ETEC), enteropathogenic ''E. coli'' (EPEC), enteroinvasive ''E. coli'' (EIEC), enteroaggregative ''E. coli'' (EAEC), and diffusely adherent ''E. coli'' (DAEC).〔 Two sentences were taken from this source verbatim.〕 The best known of these strains is O157:H7, but non-O157 strains cause an estimated 36,000 illnesses, 1,000 hospitalizations and 30 deaths in the United States yearly. Food safety specialists recognize "Big Six" strains; O26, O45, O103, O111, O121, and O145.〔 A 2011 outbreak in Germany was caused by another STEC, O104:H4. This strain has both enteroaggregative and enterohemorrhagic properties. Both the O145 and O104 strains can cause hemolytic-uremic syndrome; the former strain shown to account for 2% to 51% of known HUS cases; an estimated 56% of such cases are caused by O145 and 14% by other EHEC strains. EHECs that induce bloody diarrhea lead to HUS in 10% of cases. The clinical manifestations of postdiarrheal HUS include acute renal failure, microangiopathic hemolytic anemia, and thrombocytopenia. The verocytotoxin (shiga-like toxin) can directly damage renal and endothelial cells. Thrombocytopenia occurs as platelets are consumed by clotting. Hemolytic anemia results from intravascular fibrin deposition, increased fragility of red blood cells, and fragmentation.〔 Antibiotics are of questionable value and have not shown to be of clear clinical benefit. Antibiotics that interfere with DNA synthesis, such as fluoroquinolones, have been shown to induce the Stx-bearing bacteriophage and cause increased production of toxins. Attempts to block toxin production with antibacterials which target the ribosomal protein synthesis are conceptually more attractive. Plasma exchange offers a controversial but possibly helpful treatment. The use of antimotility agents (medications that suppress diarrhea by slowing bowel transit) in children under 10 years of age or in elderly patients should be avoided, as they increase the risk of HUS with EHEC infections.〔 ==Infectivity and virulence== The infectivity or the virulence of an EHEC strain depends on several factors, including the presence of fucose in the medium, the sensing of this sugar and the activation of EHEC pathogenicity island. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Verotoxin-producing Escherichia coli」の詳細全文を読む スポンサード リンク
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