Aim: Liver dysfunction is not rare in patients with collagen disease. We sought to elucidate the clinical features of liver dysfunction in the presence of collagen disease.
Methods: We analyzed the frequency and causes of liver dysfunction in 607 patients (rheumatoid arthritis [RA], n = 220; systemic lupus erythematosus [SLE], n = 164; systemic sclerosis [SSc], n = 47; Sjögren's syndrome [SjS], n = 44; Behçet's disease, n = 43; polymyositis/dermatomyositis [PM/DM], n = 27; vasculitis syndrome, n = 25; mixed connective tissue disease [MCTD], n = 21; and adult-onset Still's disease [AOSD], n = 16).
Results: Liver dysfunction was observed in 238 (39.2%) of 607 patients showing collagen disease. Patients with AOSD (81.3%), PM/DM (51.9%) and vasculitis syndrome (48.0%) frequently displayed liver dysfunction. Liver dysfunction in collagen diseases results from many causes; drug-induced liver injury (26.1%), fatty liver (7.6%), viral hepatitis (1.3%), autoimmune hepatitis (4.2%), primary biliary cirrhosis (15.9%) and the collagen disease itself (15.5%). Conversely, primary biliary cirrhosis was a leading cause in SSc (76.1%) and SjS (70.0%). Liver dysfunction in collagen disease tended to be mild. In addition, alanine aminotransferase levels correlated positively with ferritin levels in AOSD (R = 0.708, P < 0.05). Moreover, alkaline phosphatase levels correlated positively with C reactive protein levels in vasculitis syndrome (R = 0.833, P < 0.05).
Conclusion: Liver dysfunction in the presence of collagen disease has various causes, and dysfunction associated with collagen disease reflects the activity of the collagen disease itself.