Magnetic Resonance Enterography for Suspected Inflammatory Bowel Disease in a Pediatric Population

Objectives: The aim of the study was to determine the accuracy of magnetic resonance enterography (MRE) in diagnosing and differentiating pediatric inflammatory bowel disease (IBD). The secondary aims were to determine the accuracy of MRE in grading disease activity and determine the inter-observer agreement for individual MRE parameters. Patients and Methods: Pediatric patients scheduled to undergo esophagogastroduodenoscopy, ileocolonoscopy with biopsies, and barium enteroclysis for suspected IBD were included and underwent MRE. MRE images were evaluated by 3 observers. The accuracy of MRE was calculated using the clinical diagnosis based on endoscopic, histopathological, and barium enteroclysis examinations as reference standard. Results: Thirty-three patients were available for analysis. IBD was correctly diagnosed in, respectively, 61%, 61%, and 91% of the patients by the 3 observers, with a specificity of 80%, 90%, and 60%. Differentiation between Crohn disease (CD) and ulcerative colitis (UC) was accurately done in, respectively, 67%, 53%, and 80% of patients with CD and 0%, 14%, and 43% of patients with UC. Disease activity was understaged on MRE in the majority of patients. Intraclass correlation coefficients for measurements of bowel thickness were 0.52 (observer 1-2; observer 1-3) and 0.34 (observer 2-3). Interobserver agreement on bowel wall enhancement and stenosis was moderate to good (kappa 0.59, 0.56, and 0.56 and kappa 0.62, 0.32, 0.30, respectively). Conclusions: Sensitivity and specificity values of MRE for diagnosing pediatric IBD were moderate to good. CD, but not UC, was accurately diagnosed by MRE in a large proportion of patients. Activity was understaged in a large proportion of patients. Interobserver agreement for individual MRE parameters was fair to good.