Abstract: SA-PO486

Intensive BK Virus Screening Protocol – A Single Center Experience

Session Information

Category: Transplantation

  • 1702 Transplantation: Clinical and Translational

Authors

  • Bhalla, Anshul, Tufts Medical Center, BOSTON, Massachusetts, United States
  • Goyal, Nitender, Tufts Medical Center, BOSTON, Massachusetts, United States
  • Perrone, Ronald D., Tufts Medical Center, BOSTON, Massachusetts, United States
Background

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, 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. Increased frequency of BKV monitoring can allow for early detection and guide management. We report 1 year outcomes in a single center with an intensive BKV screening protocol.

Methods

We performed a retrospective analysis of KTR between January 2014 and March 2016. BKV screening protocol included monthly plasma BKV DNA quantitative PCR for the first 12 months. BK Viremia >3-log copies/mL was considered positive. Since management was based on confirmation of the positive value, only patients (PTS) with 2 or more positive results within a 4-week period were considered to have presumptive PyVAN (PP). Information regarding incidence, treatment and outcomes of PyVAN, rejection episodes and graft and patient survival was collected.

Results

Among 77 KTR, 70 underwent screening. Median age was 51 years (range 24-75), 61% male, 66% white and 40% had a deceased-donor transplant. 15% underwent desensitization with IVIG and 93% received Thymoglobulin for Induction. Maintenance immunosuppression (IS) regimen included Tacrolimus in 93%, Mycophenolate in 84% and Steroids in 37% PTS. Delayed graft function, defined as the need for dialysis in first week, was noted in 20%. 6 PTS (9%) had biopsy proven cellular rejection in the first 12 months. PP was noted in 19 patients (27%) during the screening period. Median time from transplant to detection of BK viremia was 81 days (range 37-265). Almost all PTS (18/19, 95%) were managed with reduction of IS (most commonly, calcineurin inhibitor followed by anti-proliferative agent and steroids). IVIG was used in 3/19 patients (16%). 8 PTS (42%) underwent allograft biopsy of which 3 had BK nephropathy. 14 out of 19 PTS (74%) had resolution of BK viremia during follow up period. Graft and PTS survival was 100% at 12 months.

Conclusion

Intensive BKV screening in the 1st year post kidney transplant allows for early intervention to guide IS management with excellent graft outcomes. This strategy reduces risk of over-treatment or risk of acute rejection. Larger trials are needed to determine the optimum frequency of BKV monitoring.