[1] Natl & Kapodistrian Univ Athens, Laiko Gen Hosp, Sch Med, Dept Gastroenterol, Athens, Greece
[2] Aristotle Univ Thessaloniki, Sch Med, Dept Internal Med 4, Thessaloniki, Greece
[3] Natl & Kapodistrian Univ Athens, Sch Med, Dept Hyg, Epidemiol & Med Stat, Athens, Greece
[4] Univ Crete, Sch Med, Clin Social & Family Med, Iraklion, Greece
[5] Natl & Kapodistrian Univ Athens, Hippokratio Gen Hosp Athens, Dept Internal Med 2, Athens, Greece
[6] Agioi Anargyroi Gen & Oncol Hosp, Acad Dept Internal Med Hepatogastroenterol, Athens, Greece
[7] Greek Org Drugs OKANA, Athens, Greece
[8] Gilead Sci Hellas, Med Dept, Athens, Greece
[9] Univ Thessaly, Sch Med, Dept Med & Res Lab Internal Med, Larisa, Greece