P48 Long-term outcomes in children and young people with combined inflammatory bowel disease and hepatobiliary disease: a dual-centre experience

<h3>Objectives and Study</h3> Inflammatory bowel disease (IBD) and concomitant Hepatopancreatobiliary (HPB) disease diagnosed in childhood have been considered to have a milder IBD phenotype,^{1 2} but paradoxically are associated with increased risk of HPB malignancy and colorectal cancer later in life. <h3>Methods</h3> A retrospective analysis of patients diagnosed with concomitant IBD and HPB disease before the age of 16 years, with a follow-up period up to 30 years of age was undertaken at a linked paediatric-adult centre with a structured transition program. Demographic data alongside biochemical, histopathological, endoscopic and radiological results were collected for all patients meeting the inclusion criteria between 2014–2024. <h3>Results</h3> A total of 38 patients were identified with IBD and concomitant HPB disease, with a mean age at diagnosis of 17.2 years (range 5–30 years). 63.2% had a primary diagnosis of IBD, 26.3% presented with simultaneous IBD &amp; HPB, whereas only 10.5% had a primary HPB diagnosis. The mean time interval between diagnoses was 17.5 months (0–144). Ulcerative Colitis (UC) was the commonest IBD type (26/38 (68.4%)) (table 1). Concomitant HPB disease included Primary Sclerosing Cholangitis (PSC) (25/38 (65.8%)), Autoimmune Hepatitis (AIH) (9/38 (23.7%)) and Autoimmune Sclerosing Cholangitis (AISC) (4/38 (10.5%)). UC/PSC combination affected 50%,(19/38) UC/AIH (7/38) 18.4% (table 1). Biologic treatment for IBD was required in 65.8%, of whom 34.2% required a second biologic and 24% required further escalation. JAK-inhibitors were used in 7/38 (18.4%) and 13/38 (34.2%) achieved clinical remission with Azathioprine or 5-ASA alone. 2/38 (5.26%) with UC/PSC required a subtotal colectomy. There were no cases of colorectal cancer. In the 19 UC/PSC subtype patients, 3 (15.8%) patients developed HPB malignancy; 2/3 had intrahepatic cholangiocarcinoma, and 1/3 had gallbladder cancer. All 3 patients underwent extensive surgical resection but developed recurrence within 3 years. Palliative systemic therapy was offered, and 1 patient died aged 29 years. Non-malignant outcomes include stage 4 liver fibrosis in 1 patient with UC/AIH and liver transplantation in another patient with IBD-U/PSC. IBD/AIH/AISC subtypes were treated with prednisolone (61.5%), azathioprine (76.9%) or mycophenolate mofetil (15.4%). In our cohort, patients did not develop significant portal hypertension. <h3>Conclusion</h3> This study demonstrates the complexity of managing children and young people with concomitant IBD and HPB disease. UC/PSC is a high-risk subtype that requires intensive monitoring and structured care with implications for transition discussions about future prognosis. Consideration should be given to developing a joint IBD-Hepatology clinical review to improve care. <h3>References</h3> Ordonez, Lacaille, Canioni, <i>et al</i>. Pediatric ulcerative colitis associated with autoimmune diseases: a distinct form of inflammatory bowel disease? <i>Inflammatory Bowel Diseases</i>. 2012;18:1809–1817 Wang, Mousa, Friton, <i>et al</i>. Unique phenotypic characteristics and clinical course in patients with ulcerative colitis and primary sclerosing cholangitis: a multicenter US experience. <i>Inflammatory Bowel Diseases</i>. 2020;26(5):774–779.