Division of Nepheology, Department of Medicine, Cardinal Tien Hospital, School of Medicine, Fu-Jen Catholic University, New Taipei, Taiwan.
Bone. 2011 Dec;49(6):1306-10. doi: 10.1016/j.bone.2011.09.047. Epub 2011 Oct 1.
Secondary hyperparathyroidism (SHP) is characterized by high bone turnover, which may, in turn, result in increased release of lead from bone stores. This study investigated the effects of intravenous calcitriol on blood lead (BL) levels in patients with SHP.
Intravenous calcitriol therapy was administered for 16 wk to 28 patients who were on maintenance hemodialysis (HD) and had intact parathyroid hormone (iPTH) plasma levels of >300 pg/mL. Blood was drawn at baseline and every 4 wk for 16 wk to determine the levels of iPTH; bone remodeling markers, including bone-specific alkaline phosphatase (bAP) and type 5b tartrate-resistant acid phosphatase (TRAP); and BL.
Of the 28 patients, 25 responded to calcitriol therapy; they exhibited significant decrements in serum iPTH levels by the end of 4 wk of therapy and thereafter. After 16 wk of therapy, these patients had significant reductions in serum iPTH levels (p<0.01) and significant and parallel decreases in the levels of bAP (p<0.01), TRAP (p<0.01), and BL (p<0.01). Further analysis showed a significant positive correlation between the levels of BL and serum iPTH (r=0.34, p<0.01) and BL and serum TRAP (r=0.22, p<0.05). However, there was no significant correlation between the levels of BL and serum bAP.
Elevated levels of BL and serum bone remodeling markers, which are common features of SHP, can be effectively suppressed by calcitriol therapy. This indicates that hyperparathyroidism not only accelerates bone remodeling but may also enhance bone lead mobilization in patients on maintenance HD.
继发性甲状旁腺功能亢进症（SHP）的特征是骨转换率高，这反过来又可能导致骨骼中储存的铅释放增加。本研究探讨了静脉用骨化三醇对 SHP 患者血铅（BL）水平的影响。
对 28 名接受维持性血液透析（HD）且甲状旁腺激素（iPTH）血浆水平>300 pg/mL 的患者进行了 16 周的静脉用骨化三醇治疗。在基线和 16 周内每 4 周抽取一次血样，以确定 iPTH 水平；骨重塑标志物，包括骨碱性磷酸酶（bAP）和 5b 酒石酸抵抗酸性磷酸酶（TRAP）；和 BL。
28 名患者中，25 名对骨化三醇治疗有反应；他们在治疗的第 4 周结束时和之后的血清 iPTH 水平显著下降。经过 16 周的治疗，这些患者的血清 iPTH 水平显著降低（p<0.01），bAP（p<0.01）、TRAP（p<0.01）和 BL（p<0.01）水平平行下降。进一步分析显示，BL 水平与血清 iPTH（r=0.34，p<0.01）和 BL 与血清 TRAP（r=0.22，p<0.05）之间呈显著正相关。然而，BL 水平与血清 bAP 之间无显著相关性。
SHP 的常见特征是 BL 和血清骨重塑标志物水平升高，这些标志物可以通过骨化三醇治疗得到有效抑制。这表明甲状旁腺功能亢进不仅加速了骨重塑，而且可能增强了维持性血液透析患者的骨铅动员。
