1. Department of Clinical Microbiology and Immunology; The Children's Memorial Health Institute; Warsaw Poland
2. Department of Oncology; The Children's Memorial Health Institute; Warsaw Poland
3. Department of Anaesthesiology and Intensive Care; The Children's Memorial Health Institute; Warsaw Poland
4. Department of Gastroenterology and Hepatology; The Children's Memorial Health Institute; Warsaw Poland
5. Department of Surgery and Organ Transplantation; The Children's Memorial Health Institute; Warsaw Poland
6. Department of General Paediatrics and Nutrition; The Children's Memorial Health Institute; Warsaw Poland