G Lippi1, C Mattiuzzi2, B M Henry3. 1. Section of Clinical Biochemistry and School of Medicine, University of Verona, Verona, Italy. Electronic address: giuseppe.lippi@univr.it. 2. Service of Clinical Governance, Provincial Agency for Social and Sanitary Services (APSS), Trento, Italy. 3. Clinical Laboratory, Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.