Development of BK nephropathy in recipients of simultaneous pancreas-kidney transplantation

BACKGROUND.: BK nephropathy (BKVN) is a significant cause of graft dysfunction in kidney transplant recipients, but its course in simultaneous pancreas-kidney (SPK) recipients is less well studied. The presence of dual organs limits the ability to reduce maintenance immunosuppression, typically the first intervention in the management of BKVN. METHODS.: A single center, retrospective review was conducted of 205 SPK transplants performed from January 1, 2000 to April 30, 2006. RESULTS.: The 5-year actuarial cumulative rate of BKVN was 5.6%. Diagnosis occurred at a median of 20 months after transplant; mean serum creatinine was 2.6, and geometric mean BK serum viral load was 709,274 copies/mL at diagnosis. There was no statistical difference in the cumulative rate according to the use of induction therapy: rabbit antilymphocyte globulin (5-year rate 6.8%, 4/59), alemtuzumab (5-year rate 5.1%, 5/146). Treatment consisted of immunosuppression reduction and half received cidofovir. Eight of nine kidney allografts eventually failed, but all patients retained pancreatic allograft function. CONCLUSIONS.: BKVN occurs in 5.6% of SPK recipients. There is no difference in the cumulative rate of BKVN between patients who received alemtuzumab or rabbit antilymphocyte globulin.