Is histological remission of ulcerative colitis achievable?

Current conception of deep remission in patients with ulcerative colitis (UC) consists of clinical remission, endoscopic mucosal healing and normalization of laboratory markers. Histological remission should not be used as a primary end point for therapeutic efficacy, but instead should be considered as a marker of deep remission. The main goal of UC treatment should be focused on endoscopic healing of colon mucosa, decrease of inflammation activity, prolonged remission, absence of disease recurrence, and also histologic remission. Nevertheless, the term histologic remission has not yet been fully validated and no histologic indexes have been standardized. We need single unified definition for remission, based on multicentral studies analysis. One of important challenge is restoration of normal colon mucosal and results of multiple studies showed contradictory tests for assessing histologic remission, thus remaining an issue for further discussion.