Optimal Level of Tacrolimus to Minimize Nephrotoxicity in Liver Transplantation / 대한이식학회지

ABSTRACT

BACKGROUND: Calcineurin inhibitor-induced nephrotoxicity is the main cause of renal dysfunction after liver transplantation (LT). The aims of this study were to investigate the changes in kidney function after LT and to determine the optimal tacrolimus level in order to minimize nephrotoxicity at various time points after LT. METHODS: We enrolled 37 LT recipients with a preoperative estimated glomerular filtration rate (eGFR) > or =60 mL/min/1.73 m2 and all received immunosuppression including tacrolimus. Renal function was assessed by eGFR. eGFR and tacrolimus level were estimated at 2 weeks, 1, 3, 6, and 12 months after LT. Multivariate regression analysis was applied for determination of mean tacrolimus level minimizing the decrease in eGFR at those time periods. Age, sex, presence of diabetes or hypertension, and use of Simulect were the covariates. RESULTS: Mean eGFR showed a decrease from 88 to 58 mL/min/1.73 m2 by 3 months after LT. Thereafter, eGFR remained stationary until 1 year. By multivariate regression analysis, mean tacrolimus level minimizing the decrease in eGFR could be obtained. Decrease of eGFR was lower in 12 patients with a mean tacrolimus level below 7.96 ng/mL compared to 25 patients with a mean tacrolimus level above 7.96 ng/mL (0.29 mL/min/1.73 m2 vs. 23.38 mL/min/1.73 m2; P=0.008). CONCLUSIONS: Kidney function had declined by three months after LT. However, thereafter, it was stationary until 1 year. Renal dysfunction could be decelerated by optimizing tacrolimus level at various time points.