Prevalent Phenotypic and Genotypic Profile of Enterotoxigenic Escherichia coli among Iranian Children

Abstract

SUMMARY: Enterotoxigenic Escherichia coli (ETEC) is the most common cause of diarrhea among children. ETEC strains express colonization factors (CFs), which mediate adherence to the small intestinal epithelium and produce entrotoxins that induce diarrhea. Here, we characterized the phenotypes and genotypes of ETEC strains from 261 diarrheal stool samples from Iranian children. The prevalence of ETEC was 8.04z. Most of the isolates were positive for heat-labile and heat-stable toxins. CFA/I, CS3, CS2, and CS5 were detected from some of the clinical isolates. 33.3z of the isolates did not express CFs. The majority of ETEC isolates were identified as O127 and O128 serotypes, and 57z of the strains were resistant to more than 1 antimicrobial agent. Heat-labile enterotoxin activity was confirmed using the Y1 adrenal cell assay, rabbit ileal loop and adenylate cyclase activation tests. Regional phenotypic and genotypic characterization could help to elucidate the ecology and pathogenicity of ETEC to efficiently reduce the burden of illness brought about by ETEC. This study may lead to development of effective prophylactic measures.

Rapid and Specific Polymerase Chain Reaction-Enzyme Linked Immunosorbent Assay for Detection of Escherichia coli LT Toxin From Clinical Isolates

“…DNA probes can be used for the detection of LT-encoding genes in various samples such as stool and environmental samples. Several sensitive and specific PCR assays exist for ETEC detection (16).…”

“…Their study was based on diagnosing ST and LT genes. Nazarian et al (16) used Multiplex PCR reaction for detection ETEC toxin and colonization factors.…”

“…Furthermore, the two previously isolated ETEC strains from children with diarrhea, characterized for enterotoxin profile, were used as controls of the PCR reaction (16).…”

Immunogenicity of a Fusion Protein Comprising Coli Surface Antigen 3 and Labile B Subunit of Enterotoxigenic Escherichia coli

“…Enterotoxigenic Escherichia coli (ETEC) is mostly prevalent in developing countries, and it causes diarrhea among children [1, 2] and visitors [1-3]. Diarrhea, which is caused by ETEC infection, leads to symptoms ranging from a nearly mild indisposition to a dehydrating condition resembling cholera disease [3].…”

“…Diarrhea, which is caused by ETEC infection, leads to symptoms ranging from a nearly mild indisposition to a dehydrating condition resembling cholera disease [3]. In acute conditions [4], the ratio of death among children under five years old is 400,000 annually [2].…”