[1] Univ Bern, Dept Paediat, Bern, Switzerland
[2] Univ Dusseldorf, Ctr Child & Adolescent Hlth, Fac Med, Dept Paediat Oncol Haematol & Clin Immunol, D-40225 Dusseldorf, Germany
[3] Univ Childrens Hosp, Infect Dis Res Program, Ctr Bone Marrow Transplantat, Munster, Germany
[4] Univ Childrens Hosp, Dept Paediat Haematol Oncol, Munster, Germany
[5] Univ Bonn, Med Ctr, Childrens Hosp, Paediat Haematol & Oncol, Bonn, Germany
[6] Tech Univ Munich, Dept Paediat, D-80290 Munich, Germany
[7] Paediat Oncol Ctr, Munich, Germany
[8] Univ Kiel, Univ Med Ctr Schleswig Holstein, Dept Paediat, Kiel, Germany
[9] Gemeinschaftskrankenhaus Herdecke, Dept Paediat & Adolescent Med, Herdecke, Germany
[10] Univ Childrens Hosp, Paediat Oncol & Haematol, Homburg, Saar, Germany