1. Department of Medical and Surgical Sciences, Università Cattolica del Sacro Cuore, Roma, Italia
2. Department of Renal Medicine, Royal Free Hospital Trust and Division of Medicine, University College, London, UK
3. U.O.S. Terapia Conservativa della Malattia Renale Cronica, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia