Active management versus minimization of immunosuppressives of BK virus-associated nephropathy after a kidney transplant. 
Thus far, there is no active treatment for BK virus-associated nephropathy after a kidney transplant that has proven to be effective.  We sought to assess the effectiveness of treatment with leflunomide, intravenous immunoglobulin, and ciprofloxacin on graft outcome after 1 year compared with a historical group treated with reduced immunosuppressive medications strategy.  Group 1 (n = 19) was composed of kidney transplant recipients with twice positive BK virus-polymerase chain reaction in urine and blood who underwent graft biopsy to confirm BK virus-associated nephropathy.  Once BK virus-associated nephropathy was diagnosed, antimetabolite (mycophenolate mofetil or azathioprine) was changed to leflunomide, and intravenous immunoglobulin and oral ciprofloxacin were given.  Group 2 (n = 14) was composed of BK virus-associated nephropathy patients treated conventionally with reduced immunosuppressive medications.  Thirty-three patients were treated, 23 were males (70%), there were 15 were deceased donors (45.5%), 15 were diabetics (45.5%), mean human leukocyte antigen mismatches were 3.76, seven had a zero DR mismatch (21.2%), and 8 were CW7 negative (24.2%).  All patients received induction therapy (thymoglobulin in 22 [66.6%]), 7 had delayed graft function (21.2%) and 18 received antirejection therapy before receiving BK virusassociated nephropathy diagnosis (52.9%).  Maintenance immunosuppression was prednisolone and mycophenolate mofetil (2 g/d) in 31 patients (94%), and tacrolimus in 13 (39.4%).  Tacrolimus was given to 12 patients in group 1 (63.1%), while sirolimus was given to 7 patients in group 2 (50%).  One graft was lost in each group by the end of the study, and 1 patient died with functioning graft in group 2.  No significant difference existed in 1-year graft outcomes between treatment of BK virus-associated nephropathy by reduction of immunosuppressive medications or actively by leflunomide, intravenous immunoglobulin, and ciprofloxacin.