P1748PARATHYROIDECTOMY REMAINS EFFECTIVE FOR TREATING TERTIARY HYPERPARATHYROIDISM: LONG-TERM RESULTS OF A RANDOMIZED STUDY

Abstract

Abstract Background and Aims Tertiary hyperparathyroidism is a common cause of hypercalcemia after kidney transplant (KT) and has been associated with renal dysfunction, loss bone mineral density and increased risk of fracture, vascular calcification, and increased risk of cardiovascular events. Long clinical management remains controversial. The aim of this study is to evaluate the long-term effectiveness and safety of parathyroidectomy versus cinacalcet in patients with persistent hyperparathyroidism. Method A 12-month prospective, multicenter, randomized study demonstrated than subtotal parathyroidectomy is more effective than cinacalcet for controlling hypercalcemia. Now, we evaluate in the same cohort of patients if this effect is maintained after 5 years of follow-up. Laboratory assessment included serum calcium, serum phosphate, intact parathyroid hormone (iPTH), calcidiol levels, estimated glomerular filtration rate and proteinuria at 2, 3, 4 and 5 year follow-up. Therapeutic details about the use of vitamin D, calcium supplementation and phosphate binders were compiled. Fragility fractures were also collected. Results In total, 24 patients had data available at 5 years, 13 in the cinacalcet group and 11 in the parathyroidectomy group. At 5 years, six of 13 patients in the cinacalcet group and ten of 11 patients in the parathyroidectomy group (p=0.015) showed normocalcemia (Figure 1). Subtotal parathyroidectomy retained a greater reduction of iPTH compared with cinacalcet group (Figure 2). No differences were observed in kidney function and incidence of fragility fractures between both groups. In relation of treatment, 8 of 13 patients in cinacalcet group maintained treatment with cinacalcet after 5 years follow-up. Conclusion Subtotal parathyroidectomy is more effective in long term to maintain normal serum calcium and iPTH compared with cinacalcet in kidney transplant patients with tertiary hyperparathyroidism.