Calcium metabolism changes after transplantation

"Abnormalities in serum calcium, phosphorus, and parathyroid hormone concentrations are common in patients with chronic kidney disease and have been associated with increased morbidity and mortality. Together with abormalities in bone metabolism and/or extra-skeletal calcification, these biochemical abnormalities constitute a systemic syndrome known as CKD mineral and bone disorder (MBD). Although it has long been believed that successful kidney transplantation to a large extent solves the problem, emerging evidence indicates that successful renal transplantation only changes its phenotype", Dr. Dr. Pieter Evenepoel (Leuven, Belgium) reports in Nieren- und Hochdruckkrankheiten 41/6.

"Posttransplant CKD - mineral and bone disorder reflects the effects of immunosuppression, previous MBD persisting after Transplantation and de novo MBD. The contribution of each changes over time."

"Serum calcium levels follow a biphasic pattern after successful renal transplantation. After an abrupt decline during the immediate postoperative period, serum calcium levels show a steady increase to reach a peak at Month 3 to 6. Transient hypercalcemia is observed in up to 66% of the renal transplant recipients.

Posttransplant hypercalcemia is mainly due to persistent hyperparathyreoidism. Several lines of evidence support the hypothesis that hypercalcemia contributes to adverse outcomes, including nephrocalcinosis and vascular calcification. Persistent hypercalcemia also predicts more severe bone mineral density loss in renal transplant recipients. Therapy may be causal (parathyroidectomy, calcimimetics) or symptomatic."