New endoscopic approach of anti-fibrotic therapy for inflammatory bowel disease
Inflammatory bowel disease (IBD), comprised of Crohn’s disease (CD) and ulcerative colitis (UC), is a chronic, progressive, destructive disease of the gastrointestinal tract characterized by the presence of extensive ulceration and mucosal inflammation in the gut. Despite a great progress in modern anti-inflammatory therapies including immuno-suppressants and biologics, intestinal fibrosis is a frequent complication in the natural history of IBD, as up to one-third of CD patients and about 5% of UC patients develop strictures in the clinical course of the disease (1-12). In CD, chronic inflammation induces transmural damage which causes accumulation of extracellular matrix (ECM) and expansion of mesenchymal cells, finally leading to intestinal strictures. In UC, increased amount of collagen and thickening of the muscularis mucosa have been identified in the colon, with consequent shortening and increased rigidity of the colon. This implies that control of intestinal inflammation alone does not necessarily affect the associated fibrotic process. There are no standard anti-fibrotic medical treatments for IBD, and dilation of intestinal strictures with endoscopy or surgical treatment plays an important role in managing the strictures of IBD (3-10). Therefore, treatment goals of IBD include not only symptom control alone but prevention of intestinal fibrosis with structural bowel damage, that is, bowel tissue remodeling (11,12).