The cornerstone of therapy is reduction in immunosuppression. A recent surge in<unk> AN correlates with use of potent immunosuppressant drugs, such as tacrolimus and mycophenolate mofetil (MMF). Studies have not shown any correlation between<unk> AN and a single immunosuppressive agent but rather the overall immunosuppressive load. * No guidelines or drug levels and doses exist for proper reduction of immunosuppressants in<unk> AN * Most common methods: # Withdrawal of MMF or tacrolimus # Replacement of tacrolimus by cyclosporine # Overall reduction of immunosuppressive load # Some cyclosporine trough levels reported to be reduced to 100–150 ng/ml and tacrolimus levels reduced to 3–5 ng/ml * Retrospective analysis of 67 patients concluded graft survival was similar between reduction and discontinuation of agents. * Single center study showed renal allografts were preserved in 8/8 individuals managed with reduction in immunosuppression while graft loss occurred in 8/12 patients treated with an increase in therapy for what was thought to be organ rejection. Other therapeutic options include Leflunomide, Cidofovir, IVIG, and the fluoroquinolones. Leflunomide, a pyrimidine synthesis inhibitor is now generally accepted as the second treatment option behind reduction of immunosuppression. Leflunomide in<unk> AN The rationale behind using leflunomide in<unk> AN comes from its combined immunosuppressive and antiviral properties. Two studies consisting of 26 and 17 patients who developed<unk> AN on a three-drug regimen of tacrolimus, MMF, and steroids had their MMF replaced with leflunomide 20–60 mg daily. 84 and 88% of patients, respectively had clearance or a progressive reduction in viral load and a stabilization or improvement of graft function (7). In a study conducted by Teschner et al. in 2009, 12/13 patients who had their MMF exchanged with leflunomide cleared the<unk>  by 109 days. In a case series, there was improvement or stabilization in 23/26 patients with<unk> AN after switching MMF to leflunomide. There are no dosing guidelines for leflunomide in<unk> AN. Patient to patient variability has made dosing and monitoring of leflunomide extremely difficult. * Study of 26 and 17 patients were dosed between 20 mg/day and 60 mg/day with trough levels of 50—100 µg/ml. Failure was seen in patients with leflunomide plasma levels 40 µg/ml) had similar effects on the rate of viral clearance. Those with higher levels had more adverse events (hematologic, hepatic). * In the study by Teschner et al., dosages and drug concentration showed no correlation with substantial variation from person to person. * In the Teschner study, low drug concentrations were associated with decrease in viral load. This makes it difficult to determine whether or not reduction of viral load or addition of leflunomide was the cause for viral clearance. Other treatment options *Quinolone antibiotics: Ciprofloxacin (Cipro) was shown to significantly lower viral loads but no data on survival and graft loss exist. *Intravenous immunoglobulin (IVIG) has use in the treatment of infection and allograft rejection – hard to distinguish *Cidofovir has limited data and is highly nephrotoxic.
BK virus
Slow virus
Hendra virus
Sepik virus
Limestone Canyon virus
Yaba monkey tumor virus
Playa de Oro virus
Banna virus