title: Clinical features of liver dysfunction in collagen diseases.
abstract: OBJECTIVE
  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).
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Gastroenterology and Rheumatology, Fukushima Medical University School of Medicine, Fukushima, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takahashi
authors.forename: Kazumichi
authors.initials: K
authors.lastname: Abe
authors.forename: Junko
authors.initials: J
authors.lastname: Yokokawa
authors.forename: Haruyo
authors.initials: H
authors.lastname: Iwadate
authors.forename: Hiroko
authors.initials: H
authors.lastname: Kobayashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Watanabe
authors.forename: Atsushi
authors.initials: A
authors.lastname: Irisawa
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Ohira