1. 1 Department of Clinical Immunology with Stem Cell Bank, University Hospital “Alexandrovska”, National Expert Center for PID, Medical University – Sofia , Bulgaria
2. 2 Department of Propaedeutics of Internal Diseases, University Hospital “Alexandrovska”, Medical University – Sofia , Bulgaria
3. 3 Department of Surgery, University Hospital “Alexandrovska”, Medical University – Sofia , Bulgaria
4. 4 Department of Occupational Medicine, Faculty of Public Health, Medical University – Sofia , Bulgaria