ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005


The Latest on X

Kidney Week

Please note that you are viewing an archived section from 2023 and some content may be unavailable. To unlock all content for 2023, please visit the archives.

Abstract: TH-PO843

A National Retrospective Cohort Study of BK Viraemia in Renal Transplant Recipients

Session Information

Category: Transplantation

  • 2102 Transplantation: Clinical


  • Clince, Michelle, Beaumont Hospital, Dublin, Ireland
  • Sandys, Vicki K., Beaumont Hospital, Dublin, Ireland
  • Fitzpatrick, Fidelma, Beaumont Hospital, Dublin, Ireland
  • Brennan, Caoimhe, UCD Center for Research in Infectious Diseases, Dublin, Ireland
  • Conlon, Peter, Beaumont Hospital, Dublin, Ireland
  • O'kelly, Patrick, Beaumont Hospital, Dublin, Ireland
  • Conlon, Peter J., Beaumont Hospital, Dublin, Ireland

BK nephropathy is an important cause of graft dysfunction and graft loss. Treatment options are limited and involve immunosuppression reduction. In Ireland, post-transplant BK DNA is checked monthly between months 1-6 and thereafter at month 9 and 12. We examine incidence, risk factors and effect of BK viraemia on long-term graft survival.


A national retrospective cohort study of renal transplant recipients in the first 12 months post-transplant between 2011-2021 was performed using data from the National Renal Transplant Registry and the National Virus Reference Lab. Patients were followed up for a minimum of 3 months and BK viraemia was defined as >5000 DNA copies per ml (CPM). A cox proportional hazards model was used to assess risks associated with BK viraemia. Statistical analysis was performed using Stata 16 SE.


Of 1319 transplanted patients, BK surveillance rates were high across all nephrology centres (96-99% of patients had results available as per monitoring protocol). 179,14% of recipients developed BK viraemia with peak levels occuring at two months and levels falling to 1000 CPM by six months. Rates of BK viraemia were higher in males than females,145 per 1000 patients (95% CI 121-175) versus 103 per 1000 patients (95% CI 76- 141). Highest rates of BK viraemia were seen in ages 49-59 (190 per 1000 patients, 95% CI 146-247). Higher rates of biopsy-proven rejection at one year (HR 1.65 CI 1.01-1.77 p-value 0.044) was associated with BK viraemia. Neither pGEN >95% (HR 1.04 CI .61- 1.77 p value 0.896) or delayed graft function (HR1.01 CI 0.68-1.49 p-value 0.969) was associated with the development of BK viraemia. At one year the average serum creatinine was 115umol/L in recipients without BK-viraemia versus 126umol/L in those with BK-viraemia (p value 0.0017). Kaplan-Meier survival graphs demonstrated no difference in renal graft survival in those with BK viraemia than those without at 10 years. (p-value 0.37).


No significant difference in graft survival was observed in those who developed BK viraemia in the first 12 months post-transplant over a decade of transplantation in Ireland. The next step of this analysis is the examine the effect of immunosuppression changes on the development of donor specific antibodies.