1Rheumatology Unit, Metropolitan Hospital, Piraeus, Greece
2Rheumatology Unit, Sismanoglio Hospital, Athens, Greece
3National and Kapodistrian University of Athens, School of Medicine, Attikon University Hospital, Athens, Greece
4Joint Rheumatology Program, Clinical Immunology-Rheumatology Unit, 2nd Department of Medicine and Laboratory, National and Kapodistrian University of Athens, School of Medicine, Hippokration General Hospital