title: Model-based clustering of Escherichia coli O157:H7 genotypes and their potential association with clinical outcome in human infections.
abstract: This study addresses the potential association of Escherichia coli O157:H7 genetic clusters with severe clinical manifestations in humans. The genotypes used in this model-based clustering had been delineated on the basis of lineage-specific polymorphism assay, Shiga toxin-encoding bacteriophage insertion site assay, clade typing, tir (A255T) polymorphism, variant analysis of Shiga toxin 2 gene, and antiterminator Q genes. Based on this model, the distribution of genotypes among tested strains suggested the presence of 6 main genetic clusters of E. coli O157:H7 strains. Clusters 1 and 3 were observed to be more frequent among E. coli O157:H7 strains isolated from bloody diarrhea and hemolytic uremic syndrome, respectively. Consequently, our findings supported the growing evidence of the existence of distinct genotypes of E. coli O157:H7 that differ in their virulence levels to human.
authors.affiliation: Department of Bacteriology, Mycology and Immunology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt. Electronic address: mm_elhadidy@mans.edu.eg.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Elhadidy
authors.affiliation: Department of Microbiology & Immunology, Faculty of Pharmacy, Ain Shams University, African Union Organization St. Abbassia, Cairo 11566, Egypt; Department of Pharmacy Practice, School of Pharmacy, Hampton University, Kittrell Hall Hampton, VA 23668, USA.
authors.forename: Walid F
authors.initials: WF
authors.lastname: Elkhatib
authors.affiliation: Department of Microbiology, Belgian STEC/VTEC National Reference Centre for Human Microbiology, University Hospital Brussels (UZ Brussel), Laarbeeklaan, Belgium.
authors.forename: Denis
authors.initials: D
authors.lastname: Piérard
authors.affiliation: Technology and Food Science Unit, Institute for Agricultural and Fisheries Research (ILVO), Brusselsesteenweg 370, Melle 9090, Belgium.
authors.forename: Koen
authors.initials: K
authors.lastname: De Reu
authors.affiliation: Technology and Food Science Unit, Institute for Agricultural and Fisheries Research (ILVO), Brusselsesteenweg 370, Melle 9090, Belgium; Department of Pathology, Bacteriology and Poultry Diseases, Ghent University, Salisburylaan 133, Merelbeke 9820, Belgium.
authors.forename: Marc
authors.initials: M
authors.lastname: Heyndrickx
mesh_terms: D016000:Cluster Analysis; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology / Q000473:pathology; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology* / Q000473:pathology*; D019453:Escherichia coli O157 / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D005798:Genes, Bacterial; D005838:Genotype; D006463:Hemolytic-Uremic Syndrome / Q000453:epidemiology / Q000382:microbiology / Q000473:pathology; D006801:Humans; D017720:Molecular Epidemiology; D058889:Molecular Typing; D016896:Treatment Outcome
keywords: E. coli O157:H7; Genetic clusters; Severe symptoms; Virulence