Persistent hyperparathyroidism after kidney transplantation in children

Abstract

Background: Most patients with chronic kidney disease develop variable degrees of secondary hyperparathyroidism, which is resolved after kidney transplantation (KT). However, persistent hyperparathyroidism after KT in adults is reported to occur in 50% patients undergoing KT; this has not been investigated thoroughly in children. Here, we analyzed the prevalence of hyperparathyroidism after KT and its risk factors among children in a single-referral hospital. Methods: This retrospective observational study analyzed medical records of children who underwent KT between 2007 and 2020. Persistent hyperparathyroidism was defined as the median PTH level of more than 65 pg/mL; its annual prevalence, risk factors, treatment status, and association with graft outcome, were analyzed. Results: Among 153 patients, 56% were boys and their mean age was 10.5 years. The prevalence of persistent hyperparathyroidism was about 36% after 1 year, which remained stable up to 4 years after KT. The occurrence of persistent hyperparathyroidism was associated with longer pretransplant dialysis duration and hyperphosphatemia. Of the enrolled children, one underwent parathyroidectomy and 15 received cinacalcet therapy. A total of 49.6% children either had a graft failure or their eGFR was less than 60ml/min/1.732 after a median of 4.6 years of KT; hyperparathyroidism status was associated with decreased kidney function. Conclusion: Prevalence of persistent hyperparathyroidism after KT is common in children, with a considerable portion of them being treated medically or surgically. The degree of secondary hyperparathyroidism before KT may be a risk factor for development of persistent hyperparathyroidism, which has been associated with decreased graft function.