Mycophenolatmofetil - A Solution for Calcineurininhibitor-induced Hypertension in Kidney Transplanted Patients?

For more than a decade, calcineurininhibitors (CNI) have been a mainstay of immunosuppression in kidney transplantation. Improved survival rates of organ and patients in the first year after transplantation led to a new era in transplantation medicine. The long term outcome however, could not be significantly improved. For this, CNI-induced hypertension can be seen as one of the main reasons. Its incidence has increased to 67- 86% compared to 45- 55% in the pre- CNI- era. The pathomechanism underlying CNI- induced hypertension must be seen as multifactorial and the precise mechanism still remains to be elucidated. In fact, characteristic vascular changes lead to systemic and renal vasoconstriction, which results in decreased renal blood flow and is therefore the basis for the nephrotoxicity observed with these agents. Due to this knowledge, the importance of newer immunosuppressants with less negative effects on the transplanted organ as well as the whole organism increases steadily. Mycophenolate mofetil can be seen as one of those. On this background, we initiated an open, randomized, prospective, two-arm multicenter study, in which an immunosuppressive regime with calcineurininhibitors (CsA, Tac) is compared with a medication based on Mycophenolate mofetil. Patients included had to be at least transplantated for one year, with stabile renal function and a serum creatinin not over 2,5 mg/dl. The so far received drugs had to be CsA respectively Tac ( MMF, corticosteroids). Duration of the study was one year. Particularly we observed the blood pressure of the included patients. At nine time points we carried out single measurements and at three time points we did a 24-hour –monitoring of the blood pressure. 14 patients have finished their first study year so far. Two of them were randomized into the control-group, which received calcineurininhibitors + corticosteroids. The other 12 patients received as study medication Mycophenolate mofetil + corticosteroids. The results show a distinct improvement of renal function in the MMF-group, pointed out as a decreased serumcreatinin. Furthermore, 9 of the 12 MMF-treated kidney-transplanted patients underwent advancement in their bloodpressure-profil, which could be fixed as a lowered medial arterial pressure in the 24-hour-measurement, a reduce in blood pressure-lowering drugs or a correction of the circadian rhythmic or a combine of these three factors. The encouraging first results of our study will be presented in this article.