1. Fundació Puigvert, Department of Nephrology, IIB Sant Pau, RedinRen, Barcelona, Catalonia, Spain
2. Department of Dialysis, AURA Nord Saint Ouen, Saint Ouen and Department of Renal Physiology, Necker Hospital, University of Paris Descartes, Paris, France
3. Renal Unit, ASST Santi Paolo e Carlo, Department of Health Sciences, University of Milan, Milan, Italy