Current status and issues on clinical indices of inflammatory bowel diseases

Disease activity of inflammatory bowel diseases (IBD) is commonly evaluated by using clinical index (CI). In Crohn's disease (CD), CDAI is the most popular index. However, even this standardized index has some limitations. Since CDAI is mainly comprised of subjective contents, total score is strongly influenced by the status and character of the patients. If a patient has a functional disorder, CDAI rise up even without disease activity. Moreover, a few contents of CDAI (e.g., standard weight) are not defined strictly. Although there are some alternative CIs, these are not able to be established now. As for ulcerative colitis, things around CIs are more problematic. First, there are many CIs according to the users' preferences or characteristics of clinical trials. Second, there are no standardized index like CDAI in UC. And then, most of the CIs of UC were not validated precisely. Therefore, we should select the CI considering the suitability to each clinical trial. In current major clinical trial, Mayo score are commonly used for evaluation of the disease activity in UC. It is mainly because this score includes an endoscopic sub-score. Actually mucosal healing, which is considered as a treatment goal of IBD, is usually defined as Mayo endoscopic sub-score 0 or 1. However, Mayo endoscopic sub-score was not validated in spite of its' frequent use. We will present about current status and issues on CIs in this section.