BACKGROUND. Nephrotoxicity is a major side effect of calcineurin inhibitors (CNI). Earlier we reported 8% of our heart transplant recipients reaching end-stage renal failure (ESRF). Now, with an extended follow up of 20 years, we re-evaluated the development of ESRF and studied its influence on survival and the impact of polymorphisms in codon 10 and 25 of the promoter region of transforming growth factor (TGF)-β on the risk of ESRF. METHODS. In all, 465 patients were transplanted between June 1984 and June 2005. All were on maintenance CNI treatment. Development of ESRF was studied in 402/465 (86.5%) patients surviving at least one year. Their median follow up was eight years, total observation time of 3,414 years. TGF-β polymorphisms in codon 10 (Leu to Pro) and codon 25 (Arg to Pro) were analyzed with real-time polymerase chain reaction in a cohort of 237 patients, with an observation time of 2,329 years. RESULTS. Ten-year survival of patients surviving at least one year was 58.5%. Seventy-three patients (18.2%) developed ESRF. Dialysis-free survival was 60% at 15 years. The relative risk for ESRF in Pro carriers was 2.9 (CI 1.5-5.8) compared to patients with the Leu/Leu genotype (P=0.002), while Pro carriers had a RR of 2.6 (CI 1.4-4.8) compared to the Arg/Arg genotype (P=0.002). Survival of patients with ESRF was 1.5 years (median). CONCLUSION. We found a highly significant association between TGF-β polymorphisms and CNI induced ESRF after heart transplantation (HTx). Pro carriers of either codon 10 or 25 had a 2.6 to 2.9 times increased risk of developing ESRF. As ESRF after HTx results in high mortality rates these patients should no longer receive CNI-based immunosuppression.

Calcineurin inhibitor, Heart transplantation, Renal failure
dx.doi.org/10.1097/01.tp.0000250360.78553.5e, hdl.handle.net/1765/64941
Transplantation
Department of Cardiology

van de Wetering, J, Weimar, W, Balk, A.H.M.M, Roodnat, J.I, Holweg, C.T.J, Baan, C.C, … Weimar, W. (2006). The impact of transforming growth factor-β1 gene polymorphism on end-stage renal failure after heart transplantation. In Transplantation (Vol. 82, pp. 1744–1748). doi:10.1097/01.tp.0000250360.78553.5e