ESPN 51th Annual Meeting

ESPN 2018

Multicenter Analysis of Risk Factors for BKPyV-associated Nephropathy (BKPyVAN) after Pediatric Renal Transplantation
Britta Höcker 1 Lukas Schneble 1 Luisa Murer 2 Andrea Carraro 2 Lars Pape 2 Birgitta Kranz 2 Jun Oh 2 Matthias Zirngibl 2 Luca Dello Strologo 2 Anja Büscher 2 Lutz T. Weber 2 Atif Awan 2 Martin Pohl 2 Martin Bald 2 Nikoleta Printza 2 Krisztina Rusai 2 Licia Peruzzi 2 Rezan Topaloglu 2 Alexander Fichtner 1 Kai Krupka 1 Lennart Köster 1 Thomas Bruckner 2 Paul Schnitzler 2 Hans H. Hirsch 2 Burkhard Tönshoff 1


BK polyomavirus (BKPyV)-associated nephropathy (BKPyVAN) constitutes a serious cause of kidney allograft failure, but comprehensive large-scale data of pediatric renal transplant recipients are lacking.

Material and methods:

We analyzed data of 313 pediatric patients (aged 10.5 ± 5.5 years at transplantation) in the Cooperative European Paediatric Renal Transplant Initiative (CERTAIN) registry research network, with an observation period of five years. Uni- and multivariate analysis was performed to identify risk factors for BKPyV replication and biopsy-proven BKPyVAN.


In the first year post-transplant, 45.7% of patients showed BKPyV viruria and/or viremia. After five years, 15.8% had developed presumptive BKPyVAN (defined as persistent BKPyV viremia > 10^4 copies/mL), and 4.9% exhibited biopsy-proven BKPyVAN. In 12.5% of patients with presumptive, and in 21.4% of those with biopsy-proven BKPyVAN, this respective event occurred late. Therapeutic intervention led to graft function improvement in 28.6% of patients and to transplant function stabilization in 57.1% of patients. However, one recipient experienced further graft function deterioration, and another lost his graft two years post-transplant. BKPyV viremia and BKPyVAN were associated with a higher net state of immunosuppression (pediatric Vasudev score; OR 1.3, p<0.01) and with TAC-based immunosuppression (OR 3.3, p<0.001), but also with younger recipient age (OR 1.1 per year younger, p<0.001) and obstructive uropathy (OR 12.4, p<0.01) as primary renal disease, while an ureteral stent placement at transplantation was not a significant risk factor.


This until now largest study on BKPyV in pediatric renal transplant recipients has identified unique features of epidemiology and risk factors. We conclude that (i) pediatric-specific risk factors must be considered in the current clinical management of BKPyV post-transplant, and (ii) BKPyV surveillance should be considered beyond two years post-transplant in pediatric patients at higher risk.