1. Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Auenbruggerplatz 15, 8036 Graz, Austria
2. Department of Internal Medicine and Diabetology, Private Clinic Wehrle-Diakonissen, 5026 Salzburg, Austria
3. 3rd Medical Division for Metabolic Diseases and Nephrology, Hospital Hietzing, 1130 Vienna, Austria
4. Institute for Metabolic Diseases and Nephrology, Karl-Landsteiner Institute, 1130 Vienna, Austria