Early onset inflammatory bowel disease - What the radiologist needs to know.

Approximately 25% of Inflammatory Bowel Disease (IBD) patients present before the age of 18 years; early-onset IBD is defined as disease presenting before 10 years of age. Although early-onset disease is rare, it presents a particular challenge both in terms of treatment and diagnosis. There is a strong genetic component to these diseases and it is now possible to identify specific genetic mutations associated with certain patterns of early-onset IBD. All of these children require specific clinical work-up that is often performed at specialist centres. Young children with IBD, present a particular challenge to the radiologist because conventional bowel imaging techniques such as MR Enterography require general anaesthetic and other techniques such as CT or fluoroscopy must be carefully considered given the increased susceptibility to radiation in this young patient population. In this paper, we present a review of the aetiology, clinical work-up, differential diagnosis, and latest theories on the genetics of early-onset and very-early onset (<6 years) IBD. We also present our experience in the imaging of these children with particular focus on the difficulties and nuances that this group present to the radiologist.