[1] Univ Liege, Serv Chim Med, CHU Liege, Dept Clin Chem, B-4000 Liege, Belgium
[2] Glasgow Royal Infirm, Dept Clin Biochem, Glasgow G4 0SF, Lanark, Scotland
[3] Univ Liege, CHU Liege, Dept Nephrol & Dialysis, B-4000 Liege, Belgium
[4] Hop Necker Enfants Malad, Lab Explorat Fonct, Paris, France