[1] Aristotle Univ Thessaloniki, Hippolaat Gen Hosp Thessaloniki, Med Sch, Dept Internal Med 4, Thessaloniki, Greece
[2] Natl & Kapodistrian Univ Athens, Dept Internal Med 1, Laiko Gen Hosp, Med Sch, Agiou Thoma 17, Athens 11527, Greece
[3] Queen Elizabeth Univ Hosp, Glasgow, Lanark, Scotland
[4] Aristotle Univ Thessaloniki, Dept Transplant Surg, Thessaloniki, Greece
[5] Aristotle Univ Thessaloniki, Dept Hyg & Epidemiol, Med Sch, Thessaloniki, Greece