Using mTOR Inhibitors in the Prevention of BK Nephropathy

BK virus infections after kidney transplant are increasing and can result in damage to the transplanted kidney. Currently, the universally accepted treatment is to decrease the strength of the antirejection medications but it is unclear what medications should be lowered and to what extent. The investigators propose to perform a study with patients who have BK virus detected in their blood during routine screening that appears to be increasing. The investigators will use two different strategies that involve different combinations of standard anti-rejection medications at lower dosages. Patients will be assigned to one of the two groups in a random manner across the two hospitals participating in the study. Patients will be followed for at least a year to determine if one strategy was more effective than the other in preventing an increase in the number of viruses in the blood stream and whether either one was more effective in reducing the negative impact of the infection on the functioning of the transplanted kidney.