Non-alcoholic steatohepatitis or autoimmune hepatitis? Sometimes a closer look under the surface is needed.

Non-alcoholic fatty liver disease (NAFLD) is nowadays the most common liver disease worldwide. Autoimmune hepatitis (AIH) is a relatively rare disease of the liver characterised by female predominance, circulating autoantibodies, polyclonal hypergammaglobulinaemia, interface hepatitis on histology and favourable response to immunosuppression. The possibility of an additional AIH diagnosis in patients with NAFLD (NAFLD/AIH concurrence) or the presence of AIH alone instead of a supposed NAFLD diagnosis represents a challenge for clinicians. We report herein two adult patients (a 33-year-old woman and a 59-year-old man) with a previous NAFLD diagnosis who proved finally to suffer from AIH alone. These two representative cases indicate how difficult and complicated could be sometimes the diagnosis of patients with AIH highlighting the range of disease manifestations and severity while they also underline that although NAFLD is by far the most frequent chronic liver disease this could not be always the case.