Immunosuppression reduction for BK viremia is associated with de novo humoral responses, which are a risk factor for rejection and graft loss. In this pilot project, we tested a protocol of immunosuppression resumption to standard dose after viral clearance for optimal protection against rejection in patients undergoing treatment for BK viremia.Methods
Thirty-six consecutive kidney transplant recipients who developed BK viremia from 7/1/2014 until 11/18/2016 underwent immunosuppression reduction. After four weeks of absent viremia, mycophenolate mofetil (MMF) was increased by 500mg/day every two weeks up to standard dosage, followed by increase of tacrolimus trough levels to 5-7ng/mL. If viremia recurred during the increase, immunosuppression was reduced in this same stepwise fashion, with stepwise increase again after two months of negative viremia.Results
Mean tacrolimus trough level (ng/mL) was 8.3+2.7 at viremia onset, 5.3+3.6 at resolution, and 5.6+2.0 at study end date. Mean daily dose (mg) of MMF was 1574+355 at onset, 910+230 at resolution, and 1377+451 at study end date. Only one patient developed low level viremia recurrence (peak 2875 copies/mL) during the period of immunosuppression resumption that ultimately resolved.Conclusions
The results of our pilot project indicate that following BK viremia resolution, resumption of standard immunosuppression can be achieved safely without BK viremia recurrence. Larger trials with long-term follow up are required to determine whether such an approach improves long- term graft survival.Conclusions
This work was supported by the Gatorade Trust through funds distributed by the University of Florida, Division of Nephrology, Hypertension, and Renal Transplantation, and the Central Florida Kidney Center, Inc. Eminent Scholar Chair in Nephrology and Hypertension.