Primary Sclerosing Cholangitis in Children With Inflammatory Bowel Diseases Is Associated With Milder Clinical Activity But More Frequent Subclinical Inflammation and Growth Impairment.

BACKGROUND & AIMS: Although inflammatory bowel diseases (IBD) associated with primary sclerosing cholangitis (PSC) have been well characterized in adults, there have been few pediatric studies, and these were small and produced conflicting results. We investigated features of PSC-IBD in children, compared with children with IBD without PSC.

METHODS: We performed a retrospective study of 74 children with PSC-IBD, diagnosed from 2000 through 2018, who were each matched with 2 children with ulcerative colitis or IBD-unclassified (controls) based on sex, date of birth, and type of IBD. We compared IBD distribution and clinical activity (remission, medication use, hospitalization, or colectomy) and patient growth between groups. Data were extracted from each hospital contact and analyzed using mixed effects analyses or Cox proportional hazards regression, adjusting for time-dependent medication exposure.

RESULTS: Higher proportions of children with PSC-IBD had backwash ileitis, pancolitis, and rectal sparing, and more severe right-sided disease, than controls (P < .05). Patients with PSC-IBD were more likely to be treated with only 5-ASA, compared with controls (odds ratio [OR], 3.04; 95% CI, 1.44-6.41) and to have IBD in clinical remission (OR, 2.94; 95% CI, 1.78-4.87). Risk of colectomy or treatment with a biologic agent was lower in patients with PSC-IBD than controls (hazard ratio, 0.24; 95% CI, 0.12-0.52). However, determination of IBD severity based on symptoms underestimated severity based on endoscopic activity in patients with PSC-IBD. Among patients with IBD in clinical remission, those with PSC were less likely to have endoscopic remission (OR, 0.44; 95% CI, 0.20-0.96). Patients with PSC-IBD were shorter and had lower weight over time, compared with controls.

CONCLUSIONS: In a retrospective study, we found that features of IBD differed between children with vs without PSC, similar to adults. Despite the mild clinical activity of IBD in patients with PSC, lack of symptoms does not always indicate lack of mucosal inflammation. Children with PSC-IBD have greater growth impairments compared with children with ulcerative colitis or IBD-unclassified.