1. School of Medicine, University of Patras, Rion, 26504 Patras, Greece
2. Laboratory of Immunohematology, Division of Hematology, Department of Internal Medicine, Medical School, University of Patras, Rion, 26504 Patras, Greece
3. Department of Internal Medicine and Division of Infectious Diseases, University General Hospital of Patras, Rion, 26504 Patras, Greece