Clinical usefulness of endocytoscopy in the remission stage of ulcerative colitis: a pilot study

Background Histopathology can be used to detect ulcerative colitis (UC) relapse, but diagnosis of the disease activity by histopathology requires multiple biopsies to be taken. Magnifying endocytoscopy provides a method for real-time ultra-magnifying imaging. It was recently reported that the endocytoscopy system score (ECSS) correlates well with the histopathology of UC. Here we evaluated the clinical usefulness of endocytoscopy for accurately monitoring UC during remission. Methods We performed endocytoscopy on 26 patients with UC in remission that had been diagnosed by conventional colonoscopy at our institution between January and April 2013. Endocytoscopy was performed at the area of the rectum where UC had been detected with conventional endoscopy. Biopsies were also taken from the same area and histopathology was evaluated by a single pathologist according to the Matts' grading system. The correlation between the relapse rate of UC and both the ECSS and the Matts' histopathological grade was evaluated. Results The ECSS of the intestinal mucosa in UC showed a correlation with the Matts' histopathological grade (Spearman's |r| = 0.647). The patients were classified into two groups: those with an ECSS of 0-2 (Grade A, 12 cases) and those with an ECSS of 3-6 (Grade B, 10 cases). To date, three Grade B cases have relapsed and no Grade A cases have relapsed. The average post-endocytoscopy surveillance period was 446 +/- A 92 days. Conclusions The ECSS may be a predictive indicator for UC relapse since there was a correlation between the ECSS and the degree of inflammation as determined by histopathology.