Liver involvement was one of the first extraglandular manifestations to be reported in patients with primary Sjögren syndrome (SS). In the 1990s, a study of liver involvement in patients with primary SS integrated the evaluation of clinical signs of liver disease, liver function and a complete panel of autoantibodies. Recent developments in the field of hepatic and viral diseases have significantly changed the diagnostic approach to liver involvement in SS. The most recent studies have shown that, after eliminating hepatotoxic drugs and fatty liver disease, the two main causes of liver disease in primary SS are chronic viral infections and autoimmune liver diseases. The differential diagnosis of liver disease in primary SS (viral vs autoimmune) is clinically important, since the two processes require different therapeutic approaches and have different prognoses. With respect to viral infections, chronic HCV infection is the main cause of liver involvement in SS patients from the Mediterranean area, while chronic HBV infection may be the main cause of liver involvement in SS patients from Asian countries. After eliminating viral hepatitis, primary biliary cirrhosis (PBC) should be considered the main cause of liver disease in primary SS. PBC-related SS patients may have a broad spectrum of abnormalities of the liver, including having no clinical or analytical data suggestive of liver disease. Autoimmune hepatitis (AIH) is the second most frequently found autoimmune liver disease to be associated with SS (all reported cases are type I), and nearly 10% of these patients have an AIH-PBC overlap. Finally, IgG4-related disease must be investigated in patients with SS presenting with sclerosing cholangitis, especially when autoimmune pancreatitis or retroperitoneal fibrosis are also present.
Keywords: Autoimmune hepatitis; Hepatitis B virus; Hepatitis C virus; Liver disease; Primary biliary cirrhosis; Sclerosing cholangitis; Sjögren syndrome.