[1] Heidelberg Univ, Childrens Hosp, Div Pediat Nephrol, D-69120 Heidelberg, Germany
[2] Heidelberg Univ, Childrens Hosp, Dept Pediat Radiol, D-69120 Heidelberg, Germany
[3] German Canc Res Ctr, Dept Radiol, D-6900 Heidelberg, Germany
[4] Humboldt Univ, Charite, Childrens Hosp, Dept Pediat Nephrol, Berlin, Germany
[5] Tulane Univ, Sch Med, Dept Med, Cardiol Sect, New Orleans, LA 70112 USA