1. Departments of Pediatrics (B.C.J.v.d.E., M.K., J.M.W.), Leiden University Medical Center, Leiden 2300 RC, The Netherlands
2. Laboratory of Endocrinology (J.v.d.V.), University Hospital Utrecht, Utrecht 3508 GA, The Netherlands
3. Endocrinology & Metabolic Diseases (M.K., C.W.G.M.L.), Leiden University Medical Center, Leiden 2300 RC, The Netherlands