1. 2nd Department of Internal Medicine and Research Laboratory, Medical School, National & Kapodistrian University of Athens, Hippokration General Hospital
2. Gastroenterology Department, National & Kapodistrian University of Athens, Medical School, Laiko General Hospital
3. Gastroenterology Department, Alexandra General Hospital
4. Intensive Care Unit, Sismanogleio General Hospital of Athens
5. Blood Bank and Haemophilia Unit, Hippokratio General Hospital of Athens, Athens, Greece