1. Medical School, University of Patras, 26504 Patras, Greece
2. Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
3. Department of Internal Medicine and Infectious Diseases, University General Hospital of Patras, 26504 Patras, Greece
4. Department of Emergency Medicine, University Hospital ATTIKON, Medical School, National and Kapodistrian University of Athens, 12462 Athens, Greece
5. 3rd Department of Critical Care, EVGENIDIO Hospital, Medical School, National and Kapodistrian University of Athens, 11528 Athens, Greece