1. Department of Internal Medicine, Clinic of Endocrinology, University Hospital “Alexandrovska”, Medical University – Sofia, Sofia, Bulgaria;
2. Department of Internal Medicine, Clinic of Gastroenterology, University Hospital “St. Ivan Rilski”, Medical University – Sofia, Sofia, Bulgaria;
3. Department of Clinical Immunology, University Hospital Lozenetz, Sofia, Bulgaria;
4. Department of Endocrinology, Laboratory of Clinical Pathology, University Hospital “St. Ivan Rilski”, Medical University – Sofia, Sofia, Bulgaria;
5. Department of Internal Medicine, Clinic of Cardiology, University Hospital “Alexandrovska”, Medical University – Sofia, Sofia, Bulgaria;
6. Medical student, Medical Faculty, Medical University, Sofia, Bulgaria