Ahmet Bahadir Ergin, MD, Department of Endocrinology, Diabetes and Metabolism, Cleveland Clinic, Cleveland, OH, USA Amir H. Hamrahiam, MD, Department of Endocrinology, Diabetes and Metabolism, Cleveland Clinic, Cleveland, OH, USA A. Laurence Kennedy, MD, FRCP, Department of Endocrinology, Diabetes and Metabolism, Cleveland Clinic, Cleveland, OH, USAManjula K. Gupta, PhD, Department of Clinical Pathology, Cleveland Clinic Cleveland, OH, USA