Immunosuppressant-induced Susceptibility
In some renal transplant patients, the necessary use of immunosuppressive drugs has the side-effect of allowing the virus to replicate within the graft, a disease called BK nephropathy. From 1–10% of renal transplant patients progress to BK virus nephropathy (BKVN) and up to 80% of these patients lose their grafts. The onset of nephritis can occur as early as several days post-transplant to as late as 5 years.
It is also associated with ureteral stenosis and interstitial nephritis. In bone marrow transplant recipients it is notable as a cause for hemorrhagic cystitis.
Read more about this topic: BK Virus