[1] Univ Zurich, Childrens Hosp, Div Immunol Haematol Oncol BMT, Zurich, Switzerland
[2] Univ Zurich, Childrens Hosp, Div Infect Dis, Zurich, Switzerland
[3] Univ Zurich, Childrens Hosp, Div Paediat Radiol, Zurich, Switzerland
[4] Univ Zurich Hosp, Dept Radiol, Div Nucl Med, CH-8091 Zurich, Switzerland