Follow Up
All patients were followed up closely for renal functions, BK viremia, and BKVN after kidney transplantation. First BKV tests were done during 1st postoperative month. All transplanted patients were tested for BKV from their serum by polymerase chain reaction (PCR) monthly in the first year after transplantation. All the patients were followed up at the posttransplant period for at least 12 months. Cases with >500 copies/ml by two or more consecutive mea­surements were accepted as having viremia. The immunosuppression dose was reduced when there was a higher viremia load (>5,000 copies/ml). Firstly MMF was discontin­ued and the prednisolone dose was reduced. If viremia continued, the calcineurin dose was reduced. Leflunomide was used for patients with BKVN. Kidney biopsy was performed to all cases with viremia for excluding BKVN.