Renin-Angiotensin System Dual Blockade Using Angiotensin Receptor Plus Aliskiren Decreases Severe Proteinuria in Kidney Transplant Recipients

Abstract Background Renin-angiotensin system (RAS) blockade has cardioprotective and renoprotective effects in the general population; however, whether dual blockade using angiotensin-receptor blockade (ARB) plus a renin inhibitor, aliskiren, can minimize severe proteinuria in kidney transplant recipients remains undetermined. Objective To analyze the efficacy and safety of dual blockade of the RAS with an ARB and aliskiren in kidney transplant recipients with severe proteinuria and creatinine concentration 2.5 mg/dL or less. Patients and Methods This prospective study included 16 patients (mean age 56 years; 10 men [62%] who had undergone cadaveric renal transplantation between 1992 and 2004. Immunosuppression therapy included a calcineurin inhibitor in 9 patients (56%) or mammalian target of rapamycin inhibitor in 7 (44%), and mycophenolate mofetil in 15 (94%). All received high-dose ARB II (1.0–3.5 g/24 h) because of marked proteinuria, with poor response. Accordingly, 11 patients also received aliskiren, and in 5 who were receiving an angiotensin-converting enzyme inhibitor, therapy was changed to aliskiren. Mean (range) follow-up was 11 (3–18) months. Results At 3 months, proteinuria decreased by 40%, and at 6 months by 60%. In addition, mean blood pressure was decreased significantly. Renal function remained stable, as did the serum potassium concentration. A slight but significant decrease in hemoglobin concentration was observed, with no clinical repercussions. Conclusions Dual blockade of the RAS with ARB II plus aliskiren therapy demonstrated an additive effect to decrease severe proteinuria and blood pressure in kidney transplant recipients. Neither relevant adverse effects in renal function nor anemia or hyperkalemia were observed. These findings might contribute to prolonging long-term kidney graft survival.