1 University Hospital Freiburg, Renal Devision, Department of Medicine, Freiburg, Germany. Electronic address: stefan.zschiedrich@uniklinik-freiburg.de.
2 University Hospital Freiburg, Renal Devision, Department of Medicine, Freiburg, Germany.
3 Division of Nephrology, Boston Children's Hospital, Boston, MA, USA.
4 Institute for Pathology, Basel, Switzerland.
5 Department of Pathology, University Hospital Eppendorf, Hamburg, Germany.