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Kidney Week

Abstract: FR-PO1141

BK Virus Surveillance and Outcomes

Session Information

Category: Transplantation

  • 1902 Transplantation: Clinical


  • Jose, Aju, Tufts Medical Center, North Attleboro, Massachusetts, United States
  • McCallum, Wendy I., Tufts Medical Center, North Attleboro, Massachusetts, United States
  • Migliozzi, Daniel R., Tufts Medical Center, North Attleboro, Massachusetts, United States
  • Dadlani, Apaar, University of Louisville School of Medicine, Lexington, Kentucky, United States
  • Perrone, Ronald D., Tufts Medical Center, North Attleboro, Massachusetts, United States
  • Bhalla, Anshul, Johns Hopkins Hospital, Baltimore, Maryland, United States
  • Goyal, Nitender, Tufts Medical Center, North Attleboro, Massachusetts, United States

Polyoma virus associated nephropathy (PyVAN) caused by BK virus (BKV) occurs in 1-10% of kidney transplant recipients (KTR). Due to lack of effective treatment options, early screening for BKV replication is the most important tool to improve outcomes. Proposed screening strategies are based on consensus guidelines but protocols vary across centers. We report the outcomes in a single center with an intensive BKV screening protocol.


We performed a retrospective analysis of KTR between Jan 2014 and Nov 2017. We obtained monthly plasma BKV DNA PCR in the first year and every other month in the 2nd year after transplant. A BKV load of >1000 copies/mL was considered positive. Information regarding incidence, treatment and outcomes of patients with BKV, rejection episodes and graft and patient survival was collected.


Among 144 KTR, data were available for 138. There were 34 (25%) patients who developed BKV during a median 2.6-year follow-up period. Baseline characteristics of patients with BKV and no BKV were similar except that more patients in BKV group were on maintenance steroids (62% vs 32%, P 0.004). Median time from transplant to detection of BK viremia was 139 days (range 34-743). Of those who developed viremia, 30 (88%) developed BKV in 1st year. Median initial and peak viral loads were 7762 copies/ml (Range, 1044-862,198) and 26200 copies/ml (Range 1145-5,000,000) respectively. Six patients developed biopsy proven PyVAN. Almost all patients (32/34) were managed with reduction in immunosuppression (IS). The initial IS reduction was MMF in 16 patients, CNI in 8 patients and 7 patients required reduction in both CNI and MMF. IVIG was used in 6 (18%) of patients in whom viremia persisted despite decrease in IS. Over our follow-up period, 27 (79%) patients had resolution of BK viremia (<1000 copies/ml), another 4 patients had >75% reduction in viral load and only one patient developed biopsy proven rejection. No grafts were lost as a result of BKV or rejection as result of reduction in IS for BKV.


Intensive BKV screening in the 1st year post kidney transplant allows for early detection to guide IS management with excellent graft outcomes. Few patients develop BK viremia in the 2nd year and a less intense monitoring can be considered in 2nd year. Larger trials are needed to determine the optimum frequency of BKV monitoring.