Inflammatory bowel disease: one or two diseases?

Abstract

This chapter addresses the longstanding question of whether inflammatory bowel disease (IBD) is really one or two diseases. The straightforward answer is that ulcerative colitis (UC) and Crohn's disease (CD) embody separate diseases more than a single syndrome. In reality, however, the question is more complex. This chapter makes the case that there are actually many more than just two diseases under the rubric of IBD.