1. Department of Nephrology, Hypertension and Internal Medicine, University of Warmia and Mazury in Olsztyn, 10-516 Olsztyn, Poland
2. Department of Nephrology, Transplantation and Internal Medicine, Medical University of Silesia, 40-027 Katowice, Poland
3. Department of Internal Diseases and Transplant Nephrology, Medical University of Lodz, 90-419 Lodz, Poland
4. Ist Department of Nephrology and Transplantation with Dialysis Unit, Medical University of Bialystok, Zurawia 14 St., 15-540 Bialystok, Poland
5. Department of Nephrology, Hypertension and Kidney Transplantation, Central University Hospital, Medical University of Lodz, 92-213 Lodz, Poland
6. Department of Nephrology, Transplantology and Internal Medicine, Medical University of Gdansk, 80-952 Gdansk, Poland
7. Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, 50-367 Wroclaw, Poland