Letter: histological assessment of disease activity in ulcerative colitis--the problem of score evaluation and validation; authors' reply.

Abstract

We read with great interest the letter by Villanacci et al. discussing our review article on the histological assessment of disease activity in ulcerative colitis (UC).1, 2 Histological healing may be the ultimate therapeutic goal in UC.3 We agree with the authors that the terms ‘mucosal/histological healing' have to be clearly defined. In this regard, a validated scoring system was eagerly awaited to determine histological criteria defining a quiescent disease.4 Recently, we developed and validated the first histological index for UC, namely the Nancy index.5 This index is easy to use and highly reproducible and has a very good responsiveness to change.5 Interestingly, Bessissow et al. demonstrated that the presence of basal plasmacytosis predicts UC clinical relapse in patients with complete mucosal healing and recommended closer follow-up and optimisation of medical therapy in patients with basal plasmacytosis.6 The Nancy index does not include basal plasmacytosis as a separate item, but it is noteworthy that the item ‘chronic inflammation' includes basal plasmacytosis. Indeed basal plasmacytosis by itself was not a reliable criteria to assess histological disease activity in UC.5 The authors' declarations of personal and financial interests are unchanged from those in the original article.2