1. Clinic of Infectious Diseases and Hepatology; Medical University of Lodz; Lodz Poland
2. Hospital for Infectious Diseases; HIV Out-Patient Clinic; Warsaw Poland
3. Department of Infectious Diseases; Jagiellonian University Medical College; Krakow Poland
4. Department of Infectious Diseases, Hepatology and Acquired Immune Deficiencies; Wroclaw Medical University; Wroclaw Poland
5. Department of Infectious and Tropical Diseases and Immune Deficiency; Pomeranian Medical University; Szczecin Poland