Type II Autoimmune hepatitis and small duct sclerosing cholangitis in a seven years old child: an overlap syndrome?

Introduction: Autoimmune hepatitis is an inflammatory disease with multifactorial ethiopatogenesis, characterized by lymphomonocytic infiltration of liver, presence of serum autoantibodies (ANA, SMA, LKM-1) and high levels of immunoglobulins. Overlap syndromes are defined as the association of autoimmune hepatitis with cholestatic diseases such as primary biliary cirrhosis and primary sclerosing cholangitis. The boundaries of these syndromes as distinct pathological entities are still matter of debate and they could be part of a major liver autoimmune disease. Furthermore, cholestatic diseases may present even with atypical features (AMA-negative primary cirrohosis, primary sclerosing cholangitis with normal cholangiography). Case Presentation: We herein describe a case of a 7 year-old child affected by an overlap syndrome between type 2 autoimmune hepatitis and small duct primary sclerosing cholangitis. Although characterized by a severe onset, the disease showed a good response to treatment with prednisone and azathioprine. Conclusions: The association of type 2 autoimmune hepatitis and small duct primary cholangitis has been rarely reported in literature and this report adds new data on this still unclear entity.