[1] UCL, Dept Clin Biochem, Sch Med, London NW3 2QG, England
[2] Aristotle Univ Thessaloniki, Sch Med, Hippocrat Hosp, Propedeut Dept Internal Med 2, GR-54006 Thessaloniki, Greece
[3] Aristotle Univ Thessaloniki, Sch Med, Div Gastroenterol, Propedeut Dept Internal Med 1, GR-54006 Thessaloniki, Greece
[4] Univ Crete, Sch Med, Dept Internal Med, Iraklion, Greece
[5] Univ Ioannina, Sch Med, Dept Internal Med, GR-45110 Ioannina, Greece
[6] Royal Free Hampstead NHS Trust, Royal Free Hosp, Royal Free Sheila Sherlock Liver Ctr, London, England
[7] UCL, London, ON, Canada