Current Topics in TransplantationRenal transplantationImpact of Trough Levels of Tacrolimus on Kidney Function and Graft Survival in Short and Longer Periods After Renal Transplantation

•The highest incidence of acute rejection was observed in the first post-transplant year most frequent occurrence of acute rejection was in the cyclosporine group.•The average TAC levels on elapsed time after transplantation significantly decreased.•Five years after renal transplantation, there were higher TAC levels in the group with “zero” low levels than in the group with “zero” high levels.•We did not find any differences between TAC levels and groups according to the induction therapy.•We did not find any difference in graft and patient survival at posttransplant years 2 and 5.

BackgroundOptimizing immunosuppressive treatment in the early posttransplant period is important for achieving long-term graft function and survival.Material and MethodsThere were 205 renal transplant recipients involved in this study. Patients were divided into groups according to the induction therapy (no induction vs basiliximab/daclizumab vs rabbit antithymocyte globulin), maintenance therapy at the time of transplantation (tacrolimus [TAC] vs cyclosporine), the average trough TAC levels in months 4 to 6 after TO and serum creatinine 5 years after renal transplantation.ResultsThe incidence of acute rejection was significantly higher in cyclosporine than in TAC group of patients (P = .0364). The average TAC levels on elapsed time after transplantation significantly decreased (P < .0001). Five years after renal transplantation, there were higher TAC levels (5.6 ± 0.7 ng/mL) in the group with “zero” low levels than in the group with “zero” high levels (4.6 ± 1.1 ng/mL), which was statistically significant (P < .0001). We did not find any difference in graft and patient survival in posttransplant years 2 to 5 according to TAC levels or the induction treatment.ConclusionsIn our study, we have confirmed that better graft function 5 years after transplantation was connected with higher trough tacrolimus levels on elapsed time after renal transplantation.