Su1228 Diffusion-Weighted Magnetic Resonance Enterocolonography Before Treatment Predicts Remission After Anti-TNF Therapy in Crohn's Disease

Abstract

Background: In the era of biologics, mucosal healing became a therapeutic target in Crohn's disease (CD) patients, however, this outcome is difficult to evaluate in daily practice because it induce the need of repeated colonoscopies. Diffusion-weighted magnetic resonance enterocolonography (DW-MREC) has shown good accuracy to detect and assess inflammatory activity in CD [1] [2]. We aimed to assess the correlation between endoscopic lesions and DW-MREC parameters i.e. Apparent Diffusion Coefficient (ADC) and Clermont score (CS) [2].Methods: In this prospective study, all the patients underwent consecutively DW-MREC with no bowel cleansing, with no rectal enema [2] and colonoscopy within 4 weeks (mean interval=17±11 days). Radiologists were blinded from endoscopic findings and endoscopists were blinded from radiologic findings. Results are given in mean ± standard deviation. Results: Among the 43 CD patients, 9 (20.5%) had previous intestinal surgery. CDAI, CRP and fecal calprotectin value were 179±93, 31.1±8.0g/L and 1172.9±730.3μg/g, respectively. The CDEIS, SES-CD and CS were 6.8±7.1, 9.2+/-8.0 and 15.8±10.7, respectively. Mean ADC was inversely correlated with CDEIS (rho=-0.40; p=0.0067) and SES-CD (rho=-0.33; p=0.032). Considering the 194 segments (ileum=37, colorectal=159), ADC was inversely correlated with segmental CDEIS (-0.48; p 20mm (1.50±0.53)(p=0.0001). Considering the 37 ileal segments, CS correlated with ileal CDEIS (0.62; p 18.9 detected ulcerations with Se=0.79 and Spe=0.73. CS increased with the ulceration size (p=0.012). Conclusions: Although MRI correlated moderately with endoscopic scores, DW-MREC using ADC and Clermont score was highly effective to indirectly detect endoscopic ulcerations in CD. Thus, DW-MREC could lead to define MRI healing as a new treatment goal in CD, and could be easily used both in daily practice and in clinical trials. [1] Buisson A et al. Aliment Pharmacol ther 2013;37:537-45. [2] Hordonneau C et al. Am J Gastroenterol 2014;109:89-98.