Mineral Metabolism Before And After Live Donor Renal Transplantation:a Single Center Study

ObjectiveWe investigated the natural course of mineral metabolism after transplantation and its risk factors. We also discussed the role of presurgical PTH played in mineral metabolism after transplantationMethodsWe retrospectively analyzed a total of297patients who underwent live donor renal transplantation. We recorded the serum calcium, adjusted calcium and phosphorus level, serum creatinine, eGFR,ALP before transplantation as well as at1day,1week,1month,3months,6months,1year,2years, and3years after transplantation. We also measured PTH level before transplantation and separated patients into2groups:high-PTH group (PTH>600pg/mL) and non-high PTH group (PTH<=600pg/mL). We then compared the difference of mineral metabolism makers in two groups. ResultsSerum calcium level showed a biphasic pattern after kidney transplantation:an immediate postoperative decrease followed by a significant increase. Posttransplantation hypercalcemia occurred in8%and3%of subjects within and beyond lyear, respectively. The serum phosphorus level dropped dramatically during perioperative period and then increased gradually and reached a plateau at around3months after transplantation. Posttransplantation serum calcium level was associated with dialysis duration, presurgical calcium and PTH level positively, and post-transplant creatinine level negatively. Posttransplantation serum phosphorus level was associated with dialysis duration and presurgical PTH level negatively. High-PTH group tended to present higher levels of serum calcium and ALP, and lower level of serum phosphorus, and higher incidences of posttransplantation hypercalcemia and hypophosphatemia.ConclusionBoth hypercalcemia and hypophosphatemia are common after renal transplantation. The patients with moderate to severe presurgical hyperparathyroidism (PTH concentrations>/=600pg/ml) tend to present higher levels of serum calcium and ALP, and lower level of serum phosphorus, and higher incidences of posttransplantation hypercalcemia and hypophosphatemia.