Conversion from cyclosporine to azathioprine improves renal function without increased risk of graft failure.

: Thirty of 110 HLA-mismatched renal allograft recipients were converted from CsA to Aza due to CsA nephrotoxicity or side effects, persistent posttransplant ATN, noncompliance, or patient desire to reduce the cost of maintenance immunosuppression. The majority of patients studied were cadaver transplant recipients. Renal function improved significantly in all patients following conversion. Converted patients did not demonstrate an increased incidence of rejection or hospitalization for fever or infection when compared with nonconverted, matched controls. The rate of allograft loss in converted patients did not differ from that of all nonconverted patients during the study period. The monthly cost of maintenance immunosuppression was significantly less in converted patients, resulting in an annual savings of $2,489 per patient. Posttransplant conversion from CsA to Aza appears to be safe and cost-beneficial.