Rapid conversion to sirolimus for chronic progressive deterioration of the renal function in kidney allograft recipients.

The aim of this study was to evaluate the safety of conversion to sirolimus (SRL) immunosuppression among 19 renal transplant recipients (KTX) with progressive chronic renal allograft dysfunction (CRAD). Conversion to SRL was performed with concomitant sharp withdrawal of the calcineurin inhibitor (CI). SRL was added at a starting dose of 3 mg, then adjusted to obtain SRL target trough blood levels of 8 to 10 ng/mL. CI were stopped the evening before starting SRL. All patients enrolled in the study have now completed 6 months of follow-up: all are alive without acute rejection or major infection following rapid conversion to SRL. No significant change in the 6 months postconversion hematologic and hepatic profile was observed compared with the preconversion values, while significant dyslipidemia was induced. After conversion to SRL, significant amelioration of the renal function was found in 36% of patients, stabilization in 21%, and continuous deterioration in 43%. Patients whose renal function improved were found to have been converted at a significantly lower creatinine: (pre 2.6 +/- 0.9 vs post 1.9 +/- 0.2; P =.038) with respect to those patients who had continuous renal deterioration. In KTX with CRAD, sharp withdrawal of CI with concomitant conversion to SRL is safe, avoiding major infections, acute rejections, and significant side effects. Short-term amelioration of the renal function is best obtained when early conversion is performed. Long-term follow-up will be necessary to confirm these preliminary data.