Role of secondary hyperparathyroidism in the development of post-transplant acute tubular necrosis

Post-transplant cure tubular necrosis (ATN) represents the most frequent cause of delayed graft function in the immediate post-transplant period. Several causes have been associated with the development of post-transplant ATN such as donor and recipient ages, cold-warm ischemia times, HLA mismatches, and postoperative hypotension. In the present study, we retrospectively evaluated the role of secondary hyperparathyroidism and high parathyroid hormone (PTHi) blood levels in the development of post-transplant ATN. One hundred patients submitted to cadaveric renal transplant between January 1992 and March 1993 in our unit were included. Twenty-seven patients (27%) developed post-transplant ATN and seventy-three (73%) did not. Post-transplant ATN was significantly associated with gender (p < 0.01), recipient age (p < 0.01), number of transplantations (p < 0.01), time on hemodialysis (p < 0.001), cold ischemic time (p < 0.05) and PTHi levels (p < 0.001). The bivariate and multivariate statistical analyses demonstrated that the development of post-transplant ATN was significantly more frequent in females; retransplanted patients, patients with a time on dialysis of more than 5 years, recipients over 60 years old, patients with a PTHi blood level higher than 240 pg/ml (4 times normal level) and a cold ischemia time of more than 18 h. Based on these results, we conclude that high PTHi blood levels in the renal transplant recipients represent a relevant factor in the development of post-transplant ATN. The administration of intravenous pulsed of 1,25(OH)2D3 and/or a calcium channel blocker in the perioperative period could be useful to decrease the incidence and severity of post-transplant ATN in these patients.