1. School of Medicine, University of Patras, 26504 Patras, Greece
2. Department of Internal Medicine and Infectious Diseases, University General Hospital of Patras, 26504 Rio, Greece
3. Hellenic Institute for the Study of Sepsis, 11528 Athens, Greece
4. 3rd Department of Critical Care, Evgenidio Hospital, Medical School, National and Kapodistrian University of Athens, 11528 Athens, Greece