IgG4 Sclerosing Cholangitis: Entity Rarely Described in Children

Abstract

IgG4-related sclerosing cholangitis (IgG4-SC) is known in the adult patients as a steroid-responsive biliary disease, frequently associated with autoimmune pancreatitis; The diagnosis of IgG4-SC may be difficult to differentiate from primary sclerosing cholangitis (PSC) or cholangiocarcinoma; This entity is been described in the absence of pancreatic implication. It is defined by high level of serum IgG4 in contrast to primary sclerosing cholangitis. It’is morphologically characterized by dense lymphoplasmacellular infiltration, particularly IgG4+ plasma cells and CD4+ T cells and extensive fibrosis in bile duct. In patients with IgG4-related sclerosing cholangitis, response to steroid therapy is high; in patients with PSC corticosteroid therapy is unsuccessful. An Early recognition of IgG4-SC can save patients from potential harmful and unnecessary surgical interventions. In the literature, cholangiocarcinoma in patients with IgG4- related sclerosing cholangitis was not described, whereas cholangiocarcinoma develops in up to 10-30% of patients with PSC. We present the case of a 3 years old child with features of sclerosing IgG4 cholangitis with asymptomatic elevation in liver enzymes, bile duct strictures on imaging, characteristic pathology findings, elevated serum IgG4, without signs of pancreatic involvement, 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.