Extradigestive manifestations of IBD in pediatrics

Inflammatory bowel diseases (IBD) are often associated with extraintestinal manifestations (EIMs), which occur in approximately one third of patients. There is only few published data on the occurrence of these manifestations in children and adolescents, so most of the data are taken by studies in adult patients. The organs most commonly affected are joints, skin, eyes and biliary tract, although nearly every organ may be involved. Some of the EIMs are clearly related to intestinal disease activity (i.e., erythema nodosum, peripheral arthritis, orofacial lesions), whereas others occur independently (i.e., pyoderma gangrenosum, anterior uveitis/iritis, ankylosing spondylitis, primary sclerosing cholangitis). Many extraintestinal disorders may be direct inflammatory and metabolic complications of the intestinal inflammation (i.e., osteoporosis, growth retardation, nephrolithiasis, ureteral obstruction, thromboembolic disease). In this review we provide an overview on the prevalence and clinical aspects of the more commonly reported EIMs of Crohn's disease and ulcerative colitis in pediatric patients, focusing on specific issues of children affected by IBD (growth failure and metabolic osteopathy).