Endocytoscopy in real time assessment of histological and endoscopic Activity in Ulcerative colitis Travel Award

Background: Endoscopic-histological remission assessment in ulcerative colitis (UC) has become the standard of care. Endocytoscopy might improve workflow and efficiency in the evaluation of UC activity. Methods: Prospective cohort study was conducted at affiliated hospital, Sydney. UC participants were recruited for colonoscopy. Chromoendoscopy was used to enhanced cellular imaging. Demographics, disease activity, Mayo endoscopic score (MES) and endocytoscopic activity were recorded. Correlation against the MES and Nancy histological index (NHI) was conducted and validation against the ErLangen Endocytoscopy in CoLiTis (ELECT) score and endocytoscopy score (ECSS) was performed using Kappa(K) and Spearman(r) correlations. Adverse events data were recorded. Results: A total of 61 colonic bowel segments were evaluated (endoscopic improvement 69%, histological remission 64%). Endocytoscopy correlated significantly with MES using both the ECSS (K=0.57; r=0.81, P<0.001) and the ELECT (K=1.00, r=0.85, P<0.001) scores. Endocytoscopy correlated with NHI using both the ECSS (K=0.47, r=0.74, P<0.001) and ELECT (K=0.89, r=0.78, P<0.001). ELECT score demonstrated superior diagnostic performance in determining histological improvement with sensitivity, specificity, and AUROC of 96%, 100%, and 0.98 (95%CI: 0.95-1.00), versus 70%, 100%, and 0.85 (95%CI: 0.78-0.92) with ECSS. No serious adverse events were reported, apart from temporary urinary discolouration. Conclusion: Simultaneous endoscopic and histological assessment of IBD is possible using endocytoscopy, which is safe, accurate and well-tolerated. The ELECT score reflects histology significantly better than ECSS.