FP427THE CLINICAL IMPACT OF TOTAL PARATHYROIDECTOMY WITH AUTO TRANSPLANTATION IN REFRACTORY SECONDARY HYPERPARATHYROIDISM

Abstract

Introduction and Aims: Total parathyroidectomy with auto transplantation (PTx‐AT) is an alternative treatment for refractory secondary hyperparathyroidism (rSHP). Clinical outcomes and factors which exert influence in functioning of AT are not fully known. The objectives of the present prospective study were to evaluate the relations between clinical, biochemical, vascular calcification (VC) and pathological parameters and PTx‐AT outcomes in a cohort of hemodialysis patients with rSHP. Methods: 52 patients underwent to PTx‐AT with 45 (Group‐45) or 90 (Group‐90) parathyroid fragments were followed during one year. Clinical, demographic, biochemical, VC parameters and parathyroid expression of Klotho, vitamin D receptor (VDR), receptor‐1 of fibroblast growth factor (FGFR1), calcium sensing receptor (CaSR), and PCNA were analyzed. Results: 36 patients completed the study. Mortality rate was 2.7 deaths/100patients‐yr. At baseline, there were no differences between groups, except for serum phosphate (P) levels (5.1+/‐1.1 mg/dl vs. 3.8+/‐1.1 mg/dl; p=0.009). After one year, PTx‐AT controlled rSHP. Systemic PTH levels were according KDIGO recommendation in 12 (33%) patients. The type of hyperplasia did not shown correlation with evolution for hypo‐ or normoparathyroidism (p=0.292), PTH ( p=0.09) and AP (p=0.529), duration of hungry bone ( p=0.582), and parathyroid expression of PCNA (p=0.374), CaSR (p=0.704), VDR ( p=0.197), FGFR1 (p=0.243) and Klotho (p=0.105). Duration of hungry bone was correlated with baseline serum AP levels (r2=0.593, p=0.001); parathyroid expression of Klotho was correlated with vitamin D dose pre‐PTx‐AT (r2=0.811, p=0.027) and baseline P (r2=‐0.528, p=0.017). VC was correlated with baseline P (r2=0.503; p=0.028) and cumulative load of Ca (r2=0.605, p=0.006); progression of VC was detected [0.53 (0‐4) vs. 1.1 (0‐8), p=0.04]; patients who were classified as having VC score <3 or >3 points mean comparison of cumulative load of Ca shown significant difference (4,411.8+/‐3,484,1g vs. 18,020+/‐11,553.9g; p=0.023). Conclusions: PTx‐AT controlled rSHP; baseline serum AP was a better predictor of hungry bone severity than PTH levels; serum P levels and cumulative load of elemental Ca were potentially related with worsening in progression of VC; the amount of transplanted parathyroid tissue, preoperative biochemical parameters, and parathyroid expression of PCNA, CaSR, VDR, FGFR1 or Klotho did not impact on systemic serum PTH levels or evolution of hypo‐ or normoparathyroidism. Vitamin D and P can regulate parathyroid expression of Klotho. (Table Presented).