1. Department of Paediatric Bone Marrow Transplantation, Oncology, and Haematology, Wroclaw Medical University, Wrocław, Poland; Department of Paediatrics, Międzyrzecki Hospital, Międzyrzecz, Poland
2. Department of Paediatrics, Międzyrzecki Hospital, Międzyrzecz, Poland
3. Department of Paediatric Neurology, Nowa Sól Multidisciplinary Hospital, Nowa Sól, Poland