Phylogenetic and pathotype analysis of Escherichia coli stool isolates from Egyptian patients with inflammatory bowel disease

Abstract

Introduction The role of Escherichia coli in the pathogenesis of inflammatory bowel disease (IBD) is still controversial. The study aimed to investigate the pathotypes and the phylogenetic groups of E. coli in Egyptian patients with IBD in an attempt to find an association between any type or group with the severity of the disease. Methods Thirty ulcerative colitis (UC), 30 Crohn's disease (CD), and 20 control subjects with normal colonoscopy were included in a cross-sectional study. E. coli were isolated from stool samples by culture. Eight intestinal virulence genes coding for diarrheagenic E. coli were investigated using multiplex PCR. Phylogenetic grouping was performed by a triplex PCR. Antimicrobial susceptibility of all isolates was done using disc diffusion method. Results Enteroaggregative E. coli (EAEC) were identified in 25% (15/60) of IBD cases and in none of the controls (p=0.013). Out the 60 IBD cases, 30 (50%) were from phylogenetic group B2. No statistically significant differences in the distribution of E. coli phylogenetic groups were found between study groups. However, 80% of EAEC were assigned to group B2 and D. No statistically significant differences in calprotectin level or in disease severity scores were reported between the four phylogenetic groups. E. coli from both UC and CD patients showed a high rate of resistance to most antimicrobials when compared to the control group. Conclusions The identification of EAEC belonging mainly to group B2 and D in IBD cases may indicate the importance of this pathotype in the pathogenesis of IBD in Egyptian patients. Keywords E. coli, enteroaggregative, IBD, phylogenetic group. Introduction1 Inflammatory bowel disease (IBD) constitutes a group of inflammatory gastrointestinal relapsing and remitting clinical conditions, of which Crohn's disease (CD) and ulcerative colitis (UC) are the most common forms. The pathogenesis of

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Antimicrobial resistance and gene regulation in Enteroaggregative Escherichia coli from Egyptian children with diarrhoea: Similarities and differences

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