IgG4-sclerosing cholangitis in a pediatric patient

IgG4 sclerosing cholangitis (IgG4-SC) is an immune-mediated process that results in inflammation and fibrosis of the pancreatobiliary tract. Although IgG4-SC is predominantly associated with autoimmune pancreatitis, IgG4-SC as its own entity can be difficult to diagnose. Patients with IgG4-SC are typically men over the age of 60, and present clinically with obstructive jaundice, abdominal pain, and weight loss. The diagnosis of IgG4-SC may be difficult to differentiate from primary sclerosing cholangitis (PSC) or cholangiocarcinoma. IgG4-SC is morphologically characterized by dense lymphoplasmacellular infiltration, particularly IgG4+ plasma cells and CD4+ T cells, extensive fibrosis in bile duct walls, and obliterative phlebitis. In contrast to PSC, those with IgG4-SC often have elevated serum IgG4 and can be successfully treated with immunosuppression. Here, we present the first reported case of IgG4-SC in a pediatric patient with asymptomatic elevation in liver enzymes, bile duct strictures on imaging, characteristic pathology findings, elevated serum IgG4, and excellent response to corticosteroids. Pediatric gastroenterologists and hepatologists, as well as pediatric hepatopathologists, need to be aware of IgG4-SC as a disease entity. Although certain clinical and imaging findings mimic PSC, diagnosis of IgG4-SC and its appropriate treatment with corticosteroids often lead to remission and reversal of disease.