Abstract
BACKGROUND: Immune-mediated extraintestinal manifestations (IM-EIMs) are common in pediatric inflammatory bowel disease (pIBD). This systematic review and meta-analysis aimed to summarize the incidence and prevalence of IM-EIMs in pIBD. METHODS: MEDLINE, EMBASE, CENTRAL, and clinicaltrials.gov were searched up to May 6, 2024, for studies that included pIBD (2-17 years) patients diagnosed with IM-EIMs. Primary outcomes included the incidence and prevalence of IM-EIMs among pIBD. Meta-analysis included pooled proportions of IM-EIMs using DerSimonian-Laird random-effects model. RESULTS: The pooled proportion of IM-EIMs overall was 10% (95% CI, 8%-12%; I(2) = 97.2%) among 65 pIBD studies (35 343 patients). The pooled proportion of IM-EIMs was 10% (95% CI, 7%-13%; I(2) = 94.8%) among 37 Crohn’s disease (CD) studies (7657 patients), compared to 11% (95% CI, 7%-15%; I(2) = 93.3%) among 39 ulcerative colitis (UC) studies (4698 patients). Enthesitis was the highest reported individual IM-EIM (23%, 95% CI, 4%-50%; I(2) = 94.7%) in pIBD. Arthritis was the second highest reported individual IM-EIM (8%, 95% CI, 6%-10%; I(2) = 96%) in pIBD, followed by primary sclerosing cholangitis (PSC) in UC (5%, 95% CI, 4%-7%; I(2) = 81%). Uveitis, pyoderma gangrenosum, autoimmune hepatitis, and PSC in CD were the lowest reported IM-EIMs at 1% or less. The largest difference in proportions between IBD phenotypes was PSC, which was 4% higher in UC than CD. CONCLUSIONS: While musculoskeletal manifestations are common, fewer than 5% of pIBD patients experience ophthalmological, dermatological, and liver IM-EIMs. The small number of studies resulted in significant methodological and statistical heterogeneity. Multicenter collaborative efforts are needed to systematically describe the epidemiology of IM-EIMs in pIBD.