1. Division of Endocrinology, American University of Beirut Medical Center , Beirut, 1107 2020 , Lebanon
2. Division of Endocrinology, Diabetes, and Metabolism, The Johns Hopkins University School of Medicine , Baltimore, MD 21287 , USA
3. Division of Endocrinology, Calcium Metabolism and Osteoporosis Program, WHO Collaborating Center for Metabolic Bone Disorders, American University of Beirut Medical Center , Beirut, 1107 2020 , Lebanon