RIDA®GENE EHEC/EPEC is a real-time multiplex PCR for the direct, qualitative detection and differentiation of the virulence-factor genes of EHEC,STEC, EPEC, EIEC/Shigella spp. in human stool samples and cultures. RIDA®GENE EHEC/EPEC real-time multiplex PCR is intended for use as an aid in diagnosis of gastroenteritis caused by pathogenic Escherichia coli and Shigella spp., respectively.
Escherichia coli (E. coli) are gram negative, facultatively anaerobic rod bacteria which move by peritrichal flagellation and belong to the Enterobacteriaceae family. E. coli are part of the normal intestinal flora of humans and many farm animals and are generally apathogenic. Some E. coli strains are pathogenic to humans through the acquisition of certain virulence factors (eg., genes for toxins). The six known intestinal pathogenic E. coli: enterohämorrhagic E. coli(EHEC), enteropathogeic E. coli (EPEC), enterotoxic E. coli (ETEC), enteroinvasive E. coli (EIEC), EAEC enteroaggregative E. coli und diffusely adherent E. coli (DAEC) can be differentiated by the virulence factors. Enterohämorrhagic E. coli (EHEC) are currently the most important intestinal pathogenic E. coli. EHEC are a subgroup of the Shiga toxin or Verotoxin producing E. coli (STEC or VTEC) and are capable to produce two cytotoxins, Verotoxin 1 and 2. Due to the similarity of the Verotoxins to the Shiga toxin of Shigella dysenteriae, the VTEC are also called STEC. Another important diagnostic virulence factor for EHEC is the eae gene (E. coli attaching and effacing gene) encoding intimin. By the detection of the ipaH gene (invasion plasmid antigen H) EHEC/STEC can be differentiated from Shigella/EIEC. The clinical symptoms, which are caused by EHEC, range from mild diarrhoeas and severe gastroenteritis to haemorrhagic colitis which occurs in approx. 10 to 20 % of cases of infection. With 5 -10 % of infections, in babies and small children in particular as well as old patients or patients with weakened immune systems, this may also lead to a haemolytic uraemic syndrome (HUS) or thrombotic thrombocytopenic purpura (TTP) as a life-threatening post-infectious complication. Enteropathogenic E. coli (EPEC) cause particularly in infants younger than 2 years diarrhea. The virulence factor for EPEC is the eae gene.