Autoimmune Sclerosing Cholangitis: a Review of the Overlap between Autoimmune Hepatitis and Primary Sclerosing Cholangitis in Children

Abstract

Pediatric patients with autoimmune liver disease (ALD) frequently demonstrate clinical, histopathologic, cholangiographic, and serologic overlap between primary sclerosing cholangitis and autoimmune hepatitis, termed autoimmune sclerosing cholangitis (ASC). Several large, collaborative studies have shed light on the epidemiology and natural history of ASC in the last 5 years. A detailed genetic and environmental description of the pathogenesis remains lacking however. Here, we review recent advancements in knowledge on ASC in children, and their implications on the management of this rare disease. Consensus diagnostic criteria for ASC do not exist, and we recommend labeling a patient as ASC only when clinical criteria for each of primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) are separately met. Treatment of ASC is based on the lobular component of inflammation, which behaves similar to AIH and responds to standard immunosuppression regimens. The cholangiopathy of ASC behaves like PSC and currently dictates prognosis as there is no effective therapy and no response to immunosuppression. Rates of liver transplantation for ASC are identical to those of PSC. Rather than specifically labeling patients as ASC, the most important tasks for clinicians managing ALD are to detect treatable autoimmune lobular inflammation in PSC patients and to identify cholangiopathy in AIH patients with persistent biochemical abnormalities prior to therapeutic escalation.