Long-term Disease Course of Crohn's Disease: Changes in Disease Location, Phenotype, Activities, and Predictive Factors.

Crohn's disease (CD) is a chronic destructive inflammatory bowel disease that affects young people and is associated with significant morbidity. The clinical spectrum and disease course of CD are heterogeneous and often difficult to predict based on the initial presentation. In this article, changes in the disease location, behavior, clinical course during long-term follow-up, and predictive factors are reviewed. Generally, four different patterns of clinical course are discussed: remission, stable disease, chronic relapsing disease, and chronic refractory disease. Understanding the long-term disease course of CD is mandatory to reveal the underlying pathophysiology of the disease and to move toward a more optimistic disease course, such as remission or stability, and less adverse outcomes or devastating sequelae.