P146 The Toronto IBD global endoscopic reporting (TIGER) score demonstrates significant correlation with fecal calprotectin, CRP and IBD Disk in Crohn's disease patients

Zittan, E.(1,2);Steinhart, A.H.(3);Aran, H.(1);Milgrom, R.(3); Koifman, E.(1);Gralnek, I.M.(1); Zelber-Sagi, S.(2);Silverberg, M.S.(3);

(1)Emek Medical Center, Ellen and Pinchas Mamber Institute of Gastroenterology and Liver Diseases- Emek Medical Center- Afula- Israel., Afula, Israel;(2)University of Haifa, School of Public Health- Faculty of Social Welfare and Health Sciences, Haifa, Israel;(3)Mount Sinai Hospital- Zane Cohen Centre for Digestive Diseases- University of Toronto, Division of Gastroenterology- Department of Medicine, Toronto, Canada

Background

Commonly used endoscopic indices in IBD lack ability to provide overall disease burden and severity, generate low inter-observer agreement, and demonstrate incomplete validation of some scores. We developed an endoscopic reporting tool, the Toronto IBD Global Endoscopic Reporting (TIGER) score for Crohn’s disease (CD) and ulcerative colitis (UC) patients. The aim of our study was to compare the usability and validity of the TIGER score against fecal calprotectin (FC), C-reactive protein (CRP) and IBD DISK score in CD patients.  

Methods

A cohort of 60 CD patients participated in the study.  Blinded IBD experts reviewed and graded ileocolonoscopy videos. In the validation phase, the TIGER score was compared to: (1) the Simple endoscopic Score for Crohn's disease (SES-CD) as a reference standard and: (2) inflammatory biomarkers FC and CRP and (3) IBD Disk score.

Results

Inter-observer reliability per segment between reviewers was excellent: Interclass Correlation Coefficient (ICC)=0.94; [95%CI: 0.92-0.96]. For categorized TIGER score, lowest overall agreement was 96.6% [95%CI: 93.5-98.6] and lowest kappa 0.91 [95%CI: 0.84-0.98], reflecting excellent agreement.  Overall agreement per segment between SES-CD and TIGER was 91% [95%CI: 84-95] with kappa coefficient 0.77 [95%CI: 0.63-0.91]. Per subject analysis for CD yielded overall agreement of 80% [95%CI: 64-91] and kappa coefficient 0.44 [95%CI: 0.14-0.75]. There was a significant correlation between TIGER and CRP (rs = .689, p < .0083), and TIGER and FC (rs = .687, p < .0001). In addition, there was significant correlation between TIGER and IBD Disk (rs = .613, p < .0001). 

Conclusion

The TIGER score demonstrates significant correlation with FC, CRP and IBD disk score in Crohn's disease patients and thus can be used as a reliable and simple endoscopic score for CD patients to capture overall endoscopic disease burden.