Escherichia coli isolates from patients with inflammatory bowel disease: ExPEC virulence- and colicin-determinants are more frequent compared to healthy controls

Abstract A set of 178 Escherichia coli isolates taken from patients with inflammatory bowel disease (IBD) was analyzed for bacteriocin production and tested for the prevalence of 30 bacteriocin and 22 virulence factor determinants. Additionally, E. coli phylogenetic groups were also determined. Pulsed-field gel electrophoresis (PFGE) was used for exclusion of clonal character of isolates. Results were compared to data from a previously published analysis of 1283 fecal commensal E. coli isolates. The frequency of bacteriocinogenic isolates (66.9%) was significantly higher in IBD E. coli compared to fecal commensal E. coli isolates (54.2%, p  E. coli isolates, a higher prevalence of determinants for group B colicins (i.e., colicins B, D, Ia, Ib, M, and 5/10) (p  fimA , 91.0%; pap , 27.5%), cytotoxic necrotizing factor ( cnf1 , 11.2%), aerobactin synthesis ( aer , 43.3%), and the locus associated with invasivity ( ial , 9.0%) were more prevalent in IBD E. coli (p  E. coli isolates from IBD mucosal biopsies were more frequently bacteriocinogenic (84.6%, p  E. coli . PFGE analysis revealed clusters specific for IBD E. coli isolates (n = 11), for fecal isolates (n = 13), and clusters containing both IBD and fecal isolates (n = 10). ExPEC (Extraintestinal Pathogenic E. coli ) virulence and colicin determinants appear to be important characteristics of IBD E. coli isolates, especially the E. coli isolates obtained directly from biopsy samples.