title: Relationship among Shigella spp. and enteroinvasive Escherichia coli (EIEC) and their differentiation.
abstract: Shigellosis produces inflammatory reactions and ulceration on the intestinal epithelium followed by bloody or mucoid diarrhea. It is caused by enteroinvasive E. coli (EIEC) as well as any species of the genus Shigella, namely, S. dysenteriae, S. flexneri, S. boydii, and S. sonnei. This current species designation of Shigella does not specify genetic similarity. Shigella spp. could be easily differentiated from E. coli, but difficulties observed for the EIEC-Shigella differentiation as both show similar biochemical traits and can cause dysentery using the same mode of invasion. Sequencing of multiple housekeeping genes indicates that Shigella has derived on several different occasions via acquisition of the transferable forms of ancestral virulence plasmids within commensal E. coli and form a Shigella-EIEC pathovar. EIEC showed lower expression of virulence genes compared to Shigella, hence EIEC produce less severe disease than Shigella spp. Conventional microbiological techniques often lead to confusing results concerning the discrimination between EIEC and Shigella spp. The lactose permease gene (lacY) is present in all E. coli strains but absent in Shigella spp., whereas β-glucuronidase gene (uidA) is present in both E. coli and Shigella spp. Thus uidA gene and lacY gene based duplex real-time PCR assay could be used for easy identification and differentiation of Shigella spp. from E. coli and in particular EIEC.
authors.affiliation: Identification and Subtyping of Enteric Pathogens International Centre for Diarrhoeal Disease Research in Bangladesh Dhaka Bangladesh Identification and Subtyping of Enteric Pathogens, International Centre for Diarrhoeal Disease Research in Bangladesh, Dhaka, Bangladesh.
authors.forename: Abu
authors.initials: A
authors.lastname: Ud-Din
authors.affiliation: Center for Food and Water Borne Disease International Centre for Diarrhoeal Disease Research in Bangladesh Dhaka Bangladesh Center for Food and Water Borne Disease, International Centre for Diarrhoeal Disease Research in Bangladesh, Dhaka, Bangladesh.
authors.forename: Syeda
authors.initials: S
authors.lastname: Wahid
mesh_terms: D001431:Bacteriological Techniques; D003937:Diagnosis, Differential; D004405:Dysentery, Bacillary / Q000175:diagnosis / Q000382:microbiology* / Q000473:pathology; D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity*; D005798:Genes, Bacterial / Q000235:genetics; D005838:Genotype; D025202:Molecular Diagnostic Techniques; D060885:Multiplex Polymerase Chain Reaction; D060888:Real-Time Polymerase Chain Reaction; D012760:Shigella / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity*; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D037521:Virulence Factors
keywords: E. coli; Shigella; diarrhea; real-time PCR