ABSTRACT
Crohn's disease and ulcerative colitis are the most common idiopathic inflammatory bowel diseases (lffiD) and affect about 2 million people in the United States. Crohn's disease involves any portion of the alimentary tract; ulcerative colitis is limited to the large intestine. These diseases most frequently affect adolescents and young adults and impact significantly upon lifestyles and productivity. The etiologies of IIBD are unknown, but ongoing research that includes clinical observations focused on patients who have received a wide variety of empirical therapies ( 1) is leading to a holistic concept of disease pathogenesis. At the present time, immune stimulation by intestinal luminal antigens, altered permeability of the intestinal mucosal barrier, disordered regulation of host gut mucosal and systemic immune systems, generation of various soluble proinflammatory mediators within intestinal mucosa, and other local gut physiological and anatomical factors are all suspected in the etiology and pathogenesis of IIBD in genetically predisposed individuals.
