Assessment of Histological Activity in Patients with Ulcerative Colitis using Nancy Index and its Correlation with Endoscopic Score (UCEIS) – A Prospective Study

Abstract

Aims: Assessment of histological activity in patients with Ulcerative Colitis (UC) using Nancy Index (NI) and determining its correlation with endoscopic grading using Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score. Study Design: Cross sectional prospective observational study. Place and Duration of Study: Department of Medical Gastroenterology and Department of Pathology, Apollo Hospital Chennai, between March 2020 to October 2021. Methodology: Consecutive patients with UC between the age 18-80 years undergoing endoscopic examination and biopsy were enrolled. Patients with infective colitis, toxic megacolon, perforation, hemodynamic instability and patients with previous colorectal surgery were excluded. Clinical disease severity was assessed using Truelove Witts score (TLW). Whereas, endoscopic and histologic activity was graded using UCEIS and Nancy Index into remission (UCEIS-0-1, NI-0-1), mild (UCEIS- 2-4,NI -2), moderate (UCEIS - 5-6,NI - 3) and severe (UCEIS - 7-8,NI - 4). Statistical analysis was performed using Spearman’s correlation coefficient using SPSS v.25.0. Results: Our study included 85 (M:F-1.5:1) patients. Mean age at presentation was 44.25(±13.44) years and age at onset of disease 39.68 (±1.32) with a median duration of disease 2(IQR – 2.5) years. Most common symptoms at the time of presentation were blood in stool followed by mucus in stool in 64.7% and 45.9%, respectively. Most of the patients were on oral ASA preparation, 43% were on AZA and 7% on steroids. Endoscopically – E1:E2:E3 disease was seen in 29%, 47% and 24%, respectively. Correlation between UCEIS and NI was found to be very strong with r =0.85(p<0.001). 95.7% of patients in endoscopic remission also had histologic remission. No statistically significant difference was found when a UCEIS score of 0 or ≤1 was used to predict histological remission. Conclusion: Significant correlation was observed between validated endoscopic and histologic indices of severity. A UCEIS score of 0 or ≤1 both predicted histological remission. Endoscopic remission can be used as surrogate marker for histological remission.