Carolyn Abitbol

Introduction Hyperparathyroidism (HPT) can contribute to metabolic bone disease following kidney transplantation. We evaluated post‐transplant trends in intact parathyroid hormone (iPTH) and determined predictors of HPT in pediatric kidney transplant (KTx) recipients. Methods In this single‐center study, retrospective data were collected on 88 children from 2013 to 2019. Data collected included dialysis vintage, biochemical parameters, post‐transplant trends in iPTH, 25(OH)Vitamin D levels and estimated glomerular filtration rate (eGFR ml/min/1.73 m 2 ). Pre‐transplant treatment for HPT was quantified with a Treatment Burden score (TB, score range: 0‐100). After log‐transforming skewed variables (iPTH and eGFR), multivariable linear regression was performed to determine predictors of log {iPTH} at 6 and 36 months (mo) post‐transplant. Results Median age was 12.8 (range: 1.9‐20.5) years, and dialysis vintage was 11.2 (range: 0.0‐112.9) months. The majority were of Hispanic and African Ancestry (77.3%). Median post‐transplant iPTH was 69.5 (range: 1.8‐306.8) pg/ml at 6 mo with a gradual downward trend to 59.0 (range: 28.0‐445.0) pg/ml at 36 mo. Significant multivariable predictors of higher log {iPTH} post‐transplant included longer dialysis vintage, higher TB, and lower log{eGFR} at 6 mo, and higher TB, lower log{eGFR}, and deceased donor transplant at 36 mo. Conclusions Recognition of risk factors for HPT and monitoring iPTH post‐transplant may facilitate timely interventions to mitigate cardiovascular and bone disease in pediatric KTx recipients. Key Message Describe serial trends in intact PTH after kidney transplantation. Pre‐ and post‐transplant factors that contribute to persistence or re‐occurrence of hyperparathyroidism after kidney transplantation in children include longer dialysis vintage, high pre‐transplant treatment burden and decreased post‐transplant GFR. Recognition of these factors, and monitoring intact PTH after kidney transplantation, could facilitate timely interventions to mitigate cardiovascular and bone disease in children.