Baba P D Inusa1, Raffaella Colombatti2. 1. Department of Paediatric Haematology, Evelina London Children's Hospital, Guy's and St Thomas NHS Trust, London, United Kingdom. 2. Clinic of Pediatric Hematology Oncology, Department of Child and Maternal Health, Azienda Ospedaliera-Università di Padova, Italy.