1. Department of Urology, University of Florence, Florence, Italy
2. Urology Unit, Department of Surgery, University of Pisa, Pisa, Italy
3. Urology Unit, Campo di Marte Hospital, Lucca, Italy
4. Department of Urology, University of Palermo, Palermo, Italy
5. Department of Urology, University of Piemonte Orientale, Novara, Italy
6. Department of Urology, “Federico II University”, Naples, Italy
7. Sexually Transmitted Diseases Centre, Santa Maria Annunziata Hospital, Florence, Italy
8. Department of Public Health and Epidemiology, University of Florence, Florence, Italy
9. Department of Urology, Technical University of Munich, Munich, Germany