1. Departments of Nephrology & Dialysis, Internal Medicine & Radiology, Vittorio Emanuele-Ferrarotto-S. Bambino Hospital, University of Catania, Catania - Italy
2. Department of Nephrology & Dialysis, A. Manzoni Hospital, Lecco - Italy
3. Department of Nephrology & Dialysis, Bussana Hospital, USL 1 Imperiese, Bussana di San Remo - Italy
4. Department of Nephrology & Dialysis, S. Camillo Hospital, Sorgono - Italy
5. Department of Nephrology & Dialysis, Infermi Hospital, Rimini - Italy