What Distinguishes Mechanisms of Fistula and Stricture Formation

  • Michael ScharlEmail author


Wound healing is a common process in the intestinal tract, in particular during chronic intestinal inflammation. Recent studies suggested a so-called regenerative inflammation that plays a crucial role for the regeneration of injured tissue. While this self-limiting acute inflammation protects the tissue, an overwhelming and chronic ongoing inflammatory process might lead to development of fibrosis or even cancer. Intestinal fibrosis and the resulting strictures represent, in addition to fistulas, frequent complications in IBD patients. To date, treatment options for fistulas and strictures are limited and no preventive treatment for intestinal fibrosis and stricture formation has been approved. As a result, irreparable organ damage and surgery is a frequent event in IBD patients. The onset of fibrosis often precedes fistula formation in the intestinal tract suggesting a pathophysiological connection between both of the processes. Nevertheless, our understanding of the pathogenetic mechanisms underlying intestinal fibrosis and fistula development is limited. An involvement of epithelial-to-mesenchymal transition (EMT) has been demonstrated for both, intestinal fibrosis as well as fistula development. It is anticipated that fistulas and fibrosis may result from chronic and severe intestinal inflammation and deregulated wound healing mechanisms. However, current knowledge also demonstrates fundamental differences between fibrosis and fistula development. Taken together, further research efforts are clearly required to gain a better understanding of the complex pathophysiology of fistula and intestinal fibrosis development. This would finally help to foster the development of novel treatment options for those intestinal complications.


Fistula Fibrosis Wound healing Epithelial-to-mesenchymal-transition TGF IL-13 MMPs 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Gastroenterology and HepatologyUniversity Hospital Zurich, University of ZurichZurichSwitzerland

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