Copyright ©2009 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Mar 21, 2009; 15(11): 1315-1318
Published online Mar 21, 2009. doi: 10.3748/wjg.15.1315
Long-term natural history of Crohn’s disease
Hugh James Freeman
Hugh James Freeman, Department of Medicine (Gastroen-terology), University of British Columbia, Vancouver V6T 1W5, Canada
Author contributions: Freeman HJ contributed all to this paper.
Correspondence to: Dr. Hugh James Freeman, MD, FRCPC, FACP, Department of Medicine (Gastroenterology), University of British Columbia Hospital, 2211 Wesbrook Mall, Vancouver V6T 1W5, Canada. hugfree@shaw.ca
Telephone: +1-604-8227216
Fax: +1-604-8227236
Received: January 19, 2009
Revised: February 16, 2009
Accepted: December 23, 2008
Published online: March 21, 2009

Crohn’s disease is a chronic inflammatory granulomatous process that usually involves different sites in the intestinal tract. Genetic and environmental factors are thought to play a role in its etiology and pathogenesis. The disorder has a heterogeneous clinical expression and data from tertiary care settings have documented its female predominance, occasional familial nature, and high rate of stricture formation and penetrating disease. It may appear from early childhood to late adulthood, although over 80% are currently diagnosed before age 40 years, usually with terminal ileal and colonic involvement. Several studies have now shown differences in phenotypic clinical expression depending on the initial age at diagnosis, with pediatric-onset disease being more severe and more extensive with more involvement of the upper gastrointestinal tract compared to adult-onset disease. In addition, long-term studies from these tertiary care settings have documented that the disorder may evolve with time into a more complex disease with stricture formation and penetrating disease complications (i.e. fistula and abscess). Although prolonged remission with no evidence of inflammatory disease may occur, discrete periods of symptomatic and active granulomatous inflammatory disease may re-appear over many decades. Long-term studies on the natural history have also suggested that discrete events (or agents) may precipitate this granulomatous inflammatory process.

Keywords: Natural history, Crohn’s disease, Age-dependent phenotypes, Clinical behavior, Granulomatous inflammation