Fibrous intimal thickening at implantation adversely affects long-term kidney allograft function.

Background: Kidneys from marginal and older donors are increasingly used to respond to the increasing demand for kidney transplants. This study evaluated the predictive value of intimal hyperplasia, as a marker of vasculopathy, in the renal allograft at the time of transplantation (transplantation) on the subsequent graft function (7 years).

Methods: The intima/media ratio of the arterial walls (I/M) was morphometrically determined by the sectorial elliptic method, in 51 implantation biopsies. Two study groups were determined. Group 1, with I/M less than or equal to 0.47, was considered as the group with minimal vascular damage at transplantation. Group 2, with I/M more than 0.47, was considered as having vasculopathy at transplantation.

Results: During the first 15 months, the estimated glomerular filtration rate improved in group 1 from 53+/-17 to 61+/-17 mL/min/1.73 m2, whereas it decreased from 51+/-21 to 46+/-14 mL/min/1.73 m2 in group 2. From 1 year posttransplantation, the estimated glomerular filtration rate (eGFR) was significantly higher in group 1 at all time points (6 month evaluation). The difference in graft function between the two groups (mean, 11 mL/min/1.73 m2) remained unchanged between 1 and 7 years posttransplantation. Among several clinical parameters investigated, blood pressure of the recipient significantly modulates the impact of preexisting vasculopathy on graft function.

Conclusion: Our data provide evidence that donor-related vasculopathy, at the time of transplantation, has a persistent significant impact on the subsequent graft function. This effect becomes only apparent at 1 year posttransplantation and is increased in recipients with inadequately controlled blood pressure.