Low prevalence of BK virus nephropathy on nonprotocol renal biopsies in Iranian kidney transplant recipients: one center's experience and review of the literature.

Objectives: BK virus-associated nephropathy in renal transplant recipients has been increasing in frequency in recent years. This rise is probably because of widespread use of highly potent immunosuppressive regimens, and increased immunosuppression load leads to inability of the recipients to increase a successful antiviral immune response. The incidence of BK virus-associated nephropathy in different reports is between 1% and 10%, with an allograft loss in significant numbers of patients, especially when timely diagnosis and treatment is not restored.