1. Infectious Diseases Unit 1, Santa Maria Annunziata Hospital, Azienda USL Toscana Centro, Bagno a Ripoli, Florence, Italy;
2. Section of Infectious Diseases, Department of Medicine, University of Perugia, Perugia, Italy;
3. Internal Medicine Unit 1, San Giuseppe Hospital, Azienda USL Toscana Centro, Empoli, Florence, Italy;
4. Internal Medicine Unit 2, San Giuseppe Hospital, Azienda USL Toscana Centro, Empoli, Florence, Italy;
5. Internal Medicine Unit, Santa Maria Annunziata Hospital, Azienda USL Toscana Centro, Bagno a Ripoli, Florence, Italy;
6. Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy