Deep remission in inflammatory bowel disease: looking beyond symptoms.

Inflammatory bowel diseases (IBD) are chronic and disabling conditions. Accumulating evidence indicates that we need to look beyond clinical symptoms as current therapeutic strategies have not modified the course of IBD. Therapeutic goals for IBD have evolved from a mere control of symptoms to mucosal healing (MH). Achieving deep remission (clinical remission, biomarker remission and MH) might be the only way to alter disease course in IBD patients. In Crohn's disease (CD), deep remission has been recently defined as Crohn's Disease Activity Index <150 and complete MH. In ulcerative colitis (UC), there is no proposed definition of deep remission. It could be defined as clinical and endoscopic remission in UC. These definitions remain to be validated in large prospective studies. In the near future, the concept of deep remission might include transmural healing in CD and histologic healing in UC. Advances in drug development have provided highly effective treatments for IBD, making deep remission a realistic goal. Whether IBD patients may benefit by experiencing a 'deep' remission beyond the control of clinical symptoms, which might ultimately impact on important outcomes such as the need for surgery and the development of disability, needs to be evaluated in future disease modification trials.