[1] Univ Pisa, Sch Med, Dept Internal Med, I-56100 Pisa, Italy
[2] Univ Pisa, CNR, Inst Clin Physiol, Metab Unit, I-56100 Pisa, Italy
[3] Azienda Osped Careggi, Endocrinol Unit, Florence, Italy
[4] Univ Florence, I-50121 Florence, Italy
[5] Univ Genoa, Dept Pediat, G Gaslini Inst, Genoa, Italy
[6] Univ Parma, Dept Pediat, I-43100 Parma, Italy