Piergiorgio Bolasco1, Roberto Aquilani2, Stefano Murtas3. 1. Chronic Renal Failure Conservative Nutritional Treatment Group, Italian Society of Nephrology, Rome, Italy. Electronic address: pg.bolasco@gmail.com. 2. Department of Biology and Biotechnology, University of Pavia, Pavia, Italy. 3. Territorial Department of Nephrology and Dialysis, ASSL Cagliari, Cagliari, Italy.