[Changes in renal function in renal transplantation. Predictive factors for functional deterioration]

Renal transplants may undergo changes secondary to the decrease of the renal mass, the effects of rejection, and various other risk factors that contribute to the progression of renal insufficiency. We have performed a prospective study of 285 cadaveric renal transplants recipients, that were receiving various maintenance immunosuppressives regimens, to study the evolution of their renal function and to evaluate the influence of various factors in the progression of renal insufficiency. All variables were analysed in a regression model of multivariate analysis. We found a progressive increase of the serum creatinine in the studied population. The mean initial creatinine was 1.70 +/- 0.84 mg/dl and final creatinine in the study 2.17 +/- 2.06 mg/dl, difference statistically significant (p = 0.000). We calculated the increase of creatinine in each patient. We observed that 113 patients (42.2%), had stable serum creatinine but the remaining 155 patients (57.8%) had a mean increase of 0.04 +/- 0.8 mg/dl/month. We analysed the patients according to various variables. Although in most the final creatinine is significantly greater than the initial, this increase of creatinine level was not present in patients with delayed graft function, in patients with no acute rejection, in the extreme age groups, in the grafts from younger donors and in those patients without initial proteinuria. The patients transplanted from younger donor had the best renal function, without any decrease in their function during the study. The advanced age of the donor has a great negative impact in the evolution of the renal transplant. According to our study, proteinuria and its quantity is a major predictor of progressive renal insufficiency. The multivariate analysis confirms that the age of the donor and initial proteinuria predict decrease of renal function. It is important to identify the factors that they could predict a greater progression to the failure of the graft. We have the possibility of acting on them, establishing immunosuppressive strategies that reduce the deleterious effects of the calcineurin inhibitors in the recipients of grafts from older donors' and to encourage the use of drugs which reduce proteinuria.