title: Evolution of bone and plasma concentration of lanthanum in dialysis patients before, during 1 year of treatment with lanthanum carbonate and after 2 years of follow-up.
abstract: BACKGROUND
  Lanthanum carbonate (LC) has been proposed as a new phosphate binder. Presented here are the results from one centre that participated in a multicentre trial to assess the effect of treatment with LC and calcium carbonate (CC) on the evolution of renal osteodystrophy in dialysis patients. Bone biopsies were performed at baseline, after 1 year of treatment and after a further 2-year follow-up period to assess the lanthanum concentration in bone and plasma.
  
  
  METHODS
  Twenty new dialysis patients were randomized to receive LC (median dose 1250 mg) for 1 year (n = 10), followed by 2 years of CC treatment or CC (n = 10) during the whole study period (3 years).
  
  
  RESULTS
  After 36 weeks of treatment, steady state was reached with plasma lanthanum levels varying around 0.6 ng/ml. Six weeks after cessation of 1 year of treatment, the plasma lanthanum levels declined to a value of 0.17 +/- 0.12 ng/ml (P < 0.05) and after 2 years to 0.09 +/- 0.03 ng/ml. Plasma and bone lanthanum levels did not correlate with the average lanthanum dose at any time point. The mean bone concentration in patients receiving LC increased from 0.05 +/- 0.03 to 2.3 +/- 1.6 microg/g (P < 0.05) after 1 year and slightly decreased at the end of the study to 1.9 +/- 1.6 microg/g (P < 0.05).
  
  
  CONCLUSIONS
  Bone deposition after 1 year of treatment with LC is low (highest concentration: 5.5 microg/g). There is a slow release of lanthanum from its bone deposits 2 years after the discontinuation of the treatment and no association with aluminium-like bone toxicity.
authors.affiliation: Department of Nephrology, University Clinical Center, Vodnjanska 17, 1000 Skopje, Macedonia. gspas@sonet.com.mk
authors.forename: Goce B
authors.initials: GB
authors.lastname: Spasovski
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Sikole
authors.forename: Saso
authors.initials: S
authors.lastname: Gelev
authors.forename: Jelka
authors.initials: J
authors.lastname: Masin-Spasovska
authors.forename: Tony
authors.initials: T
authors.lastname: Freemont
authors.forename: Isabel
authors.initials: I
authors.lastname: Webster
authors.forename: Maggie
authors.initials: M
authors.lastname: Gill
authors.forename: Chris
authors.initials: C
authors.lastname: Jones
authors.forename: Marc E
authors.initials: ME
authors.lastname: De Broe
authors.forename: Patrick C
authors.initials: PC
authors.lastname: D'Haese
mesh_terms: D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D015415:Biomarkers; D002112:Calcifediol / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000097:blood; D012080:Chronic Kidney Disease-Mineral and Bone Disorder / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007085:Ilium / Q000737:chemistry*; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000378:metabolism / Q000628:therapy; D007811:Lanthanum / Q000009:adverse effects / Q000032:analysis* / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000378:metabolism; D010758:Phosphorus / Q000097:blood; D006435:Renal Dialysis / Q000009:adverse effects*; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D010281:Parathyroid Hormone; D010710:Phosphates; D010758:Phosphorus; C119467:lanthanum carbonate; D007811:Lanthanum; D000469:Alkaline Phosphatase; D002117:Calcitriol; D002112:Calcifediol; D002118:Calcium