Optimized Tacrolimus Therapy in the Early Stage after Renal Transplantation

Abstract

Purpose: Immunosuppressive regimen based on reduced-dose Tacrolimus (TAC) is widely accepted in the field of renal transplantation. However, optimal targetsfor TAC whole blood trough concentrations during the early period after kidney transplantation remain uncertain. Methods: A total of 184 consecutive adult renal transplant recipients with triple immunosuppression (TAC/Mycophenolate/corticosteroid) were included in this study. According to the trough level of TAC at day 7 after transplantation, patients were classified as low TAC concentration (LT, ＜10 ng/㎖, n=85), intermediate TAC concentration (IT, 10∼15 ng/㎖, n=75), and high TAC concentration (HT, ＞15 ng/㎖, n=24) groups. Rate of acute rejection, graft function and side effects of TAC within 1 yr after transplantation were evaluated. Results: There was no difference in trough concentrations of TAC at 2 weeks, 1 month, 3 months, 6 months and 12 months after transplantation among the three groups. Significantly higher incidence of acute rejection within 2 weeks after transplantation was observed in LT group compared with IT and HT groups (17.4%, 5.6% and 4.8%, respectively, P=0.037). HT patients showed significantly better estimated glomerular filtration rates until 6 months after transplantation than IT and LT patients (75.5±24.8 vs. 63.8±12.8 and 64.3±15.2 ㎖/min at 6 months, P=0.03). There was no significant difference in TAC toxicity in terms of post-transplant diabetes and renal toxicity. Conclusion: Short-term high TAC exposure immediately after kidney transplantation may provide lower incidence of acute rejection and better restoration of graft function compared with low or intermediate TAC exposure.