- 4th Department of Internal Medicine, - 4th Department of Internal Medicine, - 4th Department of Internal Medicine, - 4th Department of Internal Medicine, University Hospital of Vienna Austria - Department of Thoracic Surgery, KAT Attica General Hospital - Intensive Care Unit, Radboud University Nijmegen - Department of Internal Medicine, National and Kapodistrian University of Athens Medical School - 1 st Department of Chest Medicine, Democritus University of Thrace - Department of Critical Care Medicine, General Hospital of Thessaloniki "G. Gennimatas" - Intensive Care Unit, General Hospital of Elefsis Latseion - Intensive Care Unit, Larissa University General Hospital - Department of Internal Medicine, “Aghios Dimitrios” Thessaloniki General Hospital - Intensive Care Unit, University of Patras - Department of Internal Medicine, University of Ioannina - Department of Critical Care Medicine, General Hospital of Larissa - Intensive Care Unit, Evangelismos General Hospital of Athens - 5th Department of Internal Medicine, Tzaneio General Hospital of Piraeus - Intensive Care Unit, National and Kapodistrian University of Athens Medical School - 1 st Department of Chest Medicine, Radboud University Nijmegen - Department of Internal Medicine, National and Kapodistrian University of Athens Medical School - 1 st Department of Chest Medicine, - 4th Department of Internal Medicine, Radboud University Nijmegen - Radboud Center for Infectious Diseases (RCI) and - 4th Department of Internal Medicine