The objectives of this study is to establish the natural history of BK virus viremia and other possible opportunistic viral pathogens in renal transplants recipients.

This is a Natural History study in renal or renal-pancreas transplant recipients. In an effort to capture patients early in the course of an evolving BK virus infection and avoid patients who have already developed evidence of BKV-induced nephropathy (BKVN), this protocol will emphasize the initiation of screening in the early post-transplant period. Patients who have undergone renal or renal/pancreas transplantation within 4 weeks, but not more than 90 day previously, will be asked to participate and then consented to be enrolled in a Natural History-Surveillance period for up to approximately 24 months. Participants enrolled in this study will provide valuable natural history data regarding BKV viremia, and potentially other viral pathogen, in the post-renal transplant period. Participants will provide blood samples to undergo measurement for plasma BKV DNA by PCR approximately every 6 weeks, to be resulted in real time at the UAB Diagnostic Virology Laboratory at UAB.

Inclusion Criteria:

Renal or renal-pancreas transplant patients who are within 4 weeks and not more than 90 days post-transplant with or without qualifying BKV viremia Age greater than or equal to 18 years; Provides written informed consent.

Exclusion Criteria:

Evidence of proven or suspected BKVN by clinical or pathologic diagnostic criteria Loss of renal graft function Initiation of chronic dialysis

Male and female renal or renal-pancreas transplant recipients ages 18 and older at risk for BKV infection

24 months