Multiplex polymerase chain reaction (PCR) assay for simultaneous detection of shiga-like toxin (stx1 and stx2), intimin (eae) and invasive plasmid antigen H (ipaH) genes in diarrheagenic Escherichia coli

Abstract

Despite the fact that diarrheagenic Escherichia coli (DEC) has been identified as a major etiologic agent of diarrhea in children worldwide, few studies have been performed in Iran to evaluate the etiology of these organisms. To evaluate the etiology of shiga toxin-producing E. coli (STEC), enteropathogenic E. coli (EPEC) and enteroinvasive E. coli (EIEC) in children with diarrhea in Iran a total 300 stool specimens from children with diarrhea were tested for the detection of E.coli. Out of 300 samples, 39 were identified as E. coli by biochemical tests and were subjected for serogrouping. The most prevalent serogroups among these isolates were serogroup IV, followed by III,I and II respectively. A single multiplex polymerase chain reaction (MPCR) was designed for the detection of target genes of stx1/ stx2, eae and ipaH in DEC. The dominating strain was EPEC (55.6%), followed by STEC (25%) and EIEC (19.4%).

Key words: Multiplex polymerase chain reaction (PCR), diarrheagenic Escherichia coli, shiga-like toxin.