Changing phenotype of pediatric autoimmune liver disease in an Australian cohort

Abstract

Introduction: Autoimmune liver disease (AILD) incorporates those with primary sclerosing cholangitis (PSC), autoimmune hepatitis (AIH) and autoimmune sclerosing cholangitis (ASC), an overlap of AIH and PSC. AIH is characterized by histological evidence of interface hepatitis and positive autoantibodies. PSC is characterized by inflammation and progressive obliterative fibrosis of intrahepatic and/or extrahepatic bile ducts. Many children have AILD described in association with inflammatory bowel disease (IBD). Aims: We describe a cohort of pediatric onset AILD to highlight long-term outcomes and prognostic indicators according to AILD type, as well as the change in diagnostic type with time and increasing use of magnetic resonance cholangio-pancreatography (MRCP). Methods: A retrospective chart review was conducted from January 2000 to January 2016. Demographic and disease phenotypic data were collected at diagnosis and at any change in AILD type. Results: Data were available in 75 children, 29 (38.6%) in 2000 - 2007 and 46 (61.4%) in 2008 - 2016. Presenting AILD type was AIH in 44 (58.6%), PSC in 13 (17.3%) and ASC in 9 (12%). The relative frequency of final diagnosis of PSC and ASC increased from 10 (34.4%) in 2000 - 2007 to 25 (54.3%) in 2008 - 2016. Of 44 presenting with AIH, 4 progressed to ASC, during a median follow-up of 3.2 years. PSC and ASC related to IBD also increased from 27.5% to 50%. Of the 32 with AILD-related IBD (28 ulcerative colitis, 2 Crohn's disease, 2 early onset IBD), 17 (53%) had PSC or ASC at diagnosis, 1 (3%) had AIH at diagnosis, 9 (28%) were diagnosed prior to PSC or ASC and 5 (16%) were diagnosed at least 3 months after PSC or ASC. MRCP was performed in 34.4% (2000 - 2007) and 65.4% (2008 - 2016) of patients. Large duct disease was demonstrated in 60% and 68% in respective periods. Rate of colonoscopy in children with AILD increased from 55.1% (2000 - 2007) to 60.8% (2008 - 2016). 3 children with PSC and IBD required colectomy. 40.8% of all children with IBD had right-sided disease on colonoscopy. Portal hypertension was present at diagnosis in 47.5% of AIH and 20% of PSC and ASC patients. 53% of the total population presented with advanced fibrosis on biopsy. 5 (6.6%) progressed to liver transplant (3 ASC - IBD, 1 PSC - IBD and 1 AIH - all female) with a mean age of 7.8 years, 0.5 to 5 years after diagnosis. One patient died from pulmonary embolus secondary to recurrent PSC and active IBD. Conclusion: In pediatric AILD, the relative proportion of PSC and ASC has increased in recent times, along with increasing association with IBD. This reflects change in performance of MRCP and colonoscopy. Females diagnosed with large duct ASC and PSC with IBD have the greatest risk of liver transplant in those diagnosed with AILD. Children with large duct disease PSC in association with colitis are more likely to progress to colectomy. In children with PSC or ASC with IBD, full colonoscopy to the right colon is important for management and prognostication.L6128912922016-11-10 <br />