Supported by the grant from the Crohn's and Colitis Foundation of Canada and the University of Manitoba Graduate Fellowship.
Characterization of Escherichia coli isolated from gut biopsies of newly diagnosed patients with inflammatory bowel disease†
Article first published online: 9 DEC 2010
Copyright © 2010 Crohn's & Colitis Foundation of America, Inc.
Inflammatory Bowel Diseases
Volume 17, Issue 7, pages 1451–1463, July 2011
How to Cite
Sepehri, S., Khafipour, E., Bernstein, C. N., Coombes, B. K., Pilar, A. V., Karmali, M., Ziebell, K. and Krause, D. O. (2011), Characterization of Escherichia coli isolated from gut biopsies of newly diagnosed patients with inflammatory bowel disease. Inflamm Bowel Dis, 17: 1451–1463. doi: 10.1002/ibd.21509
- Issue published online: 14 JUN 2011
- Article first published online: 9 DEC 2010
- Manuscript Accepted: 30 AUG 2010
- Manuscript Received: 22 AUG 2010
- inflammatory bowel disease;
- Crohn's disease;
- ulcerative colitis;
- mucosal associated E. coli;
- virulence characterization
Mucosal-associated Escherichia coli may play a role in the pathogenesis of inflammatory bowel diseases (IBDs). In this study we assessed mucosal-associated E. coli in adults at the time of first diagnosis.
Materials and Methods:
E. coli were isolated from 59 right colon biopsies of 34 newly diagnosed adult IBD patients (Crohn's disease [CD] = 23, ulcerative colitis [UC] = 11) and 25 healthy controls (HC). Strains were serotyped, phylotyped into A, B1, B2, or D, and tested for their ability to survive in macrophages. The presence of various virulence factors was also assessed. The fimH subunit of type 1 fimbriae was sequenced and phylogenetically analyzed.
A total of 65 E. coli were isolated from CD (29 isolates from 23 patients), UC (11 isolates from 11 patients), and HC (25 isolates from 25 subjects). All E. coli were positive for fimH, crl, and cgsA and negative for vt1, vt2, hlyA, cnf, and eae. Significant positive associations were between CD and in between CD and afae (P = 0.002), and between UC and ompA (P = 0.02), afae (P = 0.03), and USP (P = 0.04). The B2+D phylotype was significantly associated with inflammation (P = 0.04) as it was with serine protease autotransporters (SPATE), malX, ompA, and kpsMTII (P < 0.05). Macrophage survival was the highest in UC-isolated E. coli (P = 0.04). FimH amino acid substitutions N91S, S99N, and A223V were associated with IBD (P < 0.05).
Adherent invasive E. coli are present at first diagnosis, suggesting that they may have a role in the early stages of disease onset. (Inflamm Bowel Dis 2010;)