title: Decreased blood lead levels after calcitriol treatment in hemodialysis patients with secondary hyperparathyroidism.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors: Division of Nepheology, Department of Medicine, Cardinal Tien Hospital, School of Medicine, Fu-Jen Catholic University, New Taipei, Taiwan. kuochenglu@gmail.com
authors: Kuo-Cheng
authors: KC
authors: Lu
authors: Chia-Chao
authors: CC
authors: Wu
authors: Wen-Ya
authors: WY
authors: Ma
authors: Chun-Chi
authors: CC
authors: Chen
authors: Hsin-Chi
authors: HC
authors: Wu
authors: Pauling
authors: P
authors: Chu
mesh_terms: D000135:Acid Phosphatase / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001842:Bone and Bones / Q000378:metabolism / Q000473:pathology; D002117:Calcitriol / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000097:blood* / Q000188:drug therapy*; D007527:Isoenzymes / Q000097:blood; D007854:Lead / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D006435:Renal Dialysis; D000071681:Tartrate-Resistant Acid Phosphatase
chemical_list: D015415:Biomarkers; D007527:Isoenzymes; D010281:Parathyroid Hormone; D007854:Lead; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D002117:Calcitriol