Predictors of tertiary hyperparathyroidism: Who will benefit from parathyroidectomy?

Background. Tertiary hyperparathyroidism (3 degrees HPT) is hyperparathyroidism with hypercalcemia after renal transplantation. With unclear guidelines for parathyroidectomy (PTX), this study aims to determine which renal transplant patients develop 3 degrees HPT and would benefit from PTX. Methods. We performed a retrospective review of patients who received a renal transplant between 1994 and 2013; 105 patients who underwent near total PTX (NTPTX) were compared with 180 renal transplant control patients who did not undergo NTPTX. Results. Calcium and PTH varied significantly between groups (P < .001). One year before transplant, the mean serum calcium was 9.7 +/- 1.1 mg/dL in the NTPTX group versus 9.1 +/- 0.9 mg/dL in the control group (P < .01). One month after transplant, the mean calcium in the NTPTX group was 10.4 +/- 1.1 versus 9.4 +/- 0.6 mg/dL in the control group (P < .001). One year before renal transplant, the median serum PTH level was 723 pg/mL (range, 557-919) in the NTPTX group versus 212 pg/mL (range, 160-439) in the control group (P < .01). One-month post renal transplant, the NTPTX group had a median PTH of 351 pg/mL (range, 199-497) versus 112 pg/mL (range, 73-178) pg/mL in the control group (P < .01). Conclusion. Before and after renal transplantation, PTH and calcium levels can serve as predictors of 3 degrees HPT.