Manifestations of small bowel disease in pediatric Crohn's disease on magnetic resonance enterography.

Background: We report the manifestations of Crohn's disease (CD) observed on magnetic resonance enterography (MRE) in a pediatric population at the time of CD diagnosis.

Methods: MRE of 95 consecutive pediatric patients with inflammatory bowel disease (IBD) examined in 2006-2009 were retrospectively analyzed, with documentation of findings based on type and location of the small bowel (SB) disease.

Results: In all, 51 were boys and 44 girls. 54 had CD, 31 non-CD IBD, and 10 no IBD. The most common site of SB involvement in CD was the terminal ileum seen in 29 (53.7%) patients, followed by ileum in 10 (18.5%) and jejunum in 9 (16.7%) patients. Solitary jejunal inflammation (3.7%), SB stenoses (1.9%), fistula formation (0.95%), and abscess (0.95%) were much less common. Perienteric lymphadenopathy was seen in 30 (55.6%) patients and fatty proliferation in 9 (16.7%). The most common manifestation of SB inflammation was increased contrast enhancement of bowel wall (93.5%), thickening of the bowel wall (90.3%), and derangement of bowel shape with saccular formations (25.8%).

Conclusions: MRE in the pediatric population often demonstrates increased contrast uptake, bowel wall thickening, and perienteral lymphadenopathy in CD. More chronic small bowel changes seen commonly in adults and solitary jejunal involvements are less commonly seen.