Proximal small bowel (SB) involvement in CD is associated with a more aggressive disease course and an increased need for surgery.Therefore, accurate determination of SB involvement in pediatric CD is crucial for optimal patient management. Current clinical guidelines include suggested modalities to identify SB involvement and determine management plans. Available options include small bowel series, computed tomography enterography (CTE), small bowel wireless capsule endoscopy (WCE), gadolinium enhanced MRI imaging (GAD MRI), and small bowel contrast enhanced ultrasound (US). The choice of modality is largely determined by available resources, radiation exposure risk, and physician and institutional preferences. MRE and contrast enhanced US are radiation free, while other radiologic modalities entail a risk of radiation exposure. WCE may entail a risk of capsule retention. The risk of capsule retention resulting in obstruction is increased in the context of stricturing or fistulizing disease in CD and has been estimated at 2.6% but may be greatly mitigated by patency capsule screening.~Magnetic resonance enterography (MRE) and small bowel contrast ultrasound (SICUS) have diagnostic effectiveness comparable to other radiological modalities for evaluation of CD patients. However, both studies have their own limitations, MRE is limited by expense, the availability of the requisite equipment and software, variable expertise in interpretation of the findings, and (potentially) the need for sedation in pediatric population. SICUS is similarly affected by being operator dependent with the requisite need of accumulated expertise and heightened need for cooperation during the study that can limit its use in pediatric populations.~Several diagnostic modalities have been evaluated in comparison to WCE in several pediatric and adult IBD studies. The studies conducted in children with IBD were mostly retrospective and aimed at evaluating the role of MRE and WCE for detection of SB disease. They concluded that MRE and WCE were comparable with similar sensitivities. Only three prospective studies (all European) in pediatric IBD have compared WCE and MRE modalities in identifying SB disease involvement. Two were studies in established CD and one in suspected CD and again, they suggested that the tests appear complementary for detection of active CD. The current study is the a another prospective study in children with established IBD in the United States assessing the roles of MRE and WCE in identifying SB disease involvement in IBD. This study provides evidence for capsule endoscopy in the evaluation of established disease exacerbation in patients with IBD in relation to MRE.
Most of the studies evaluating the roles of MRE and WCE conducted in pediatric patients have been retrospective with the main goal of making a diagnosis in patients with suspected IBD. The current study is the first prospective study in children with known IBD assessing the roles of MRE and WCE in identifying disease exacerbation. This study will help to identify if capsule endoscopy is superior or complementary to MRE in the evaluation of suspected disease exacerbation in IBD patients.