title: Early skeletal and biochemical alterations in pediatric chronic kidney disease.
abstract: OBJECTIVE
  The relationship between parathyroid hormone, fibroblast growth factor 23 (FGF-23), and indices of bone turnover and mineralization in children with early CKD is unknown; thus, this study characterizes the features of renal osteodystrophy and their relationship to biochemical markers of mineral metabolism.
  
  
  METHODS
  Fifty-two patients 2-21 years of age with predialysis CKD underwent tetracycline-labeled bone biopsy. Anthropomorphic measurements and biochemical values were obtained at the time of biopsy.
  
  
  RESULTS
  Serum phosphorus levels were increased in 4% of patients with stage 3 CKD and 43% of those with stage 4/5 CKD. Parathyroid hormone concentrations were elevated in 36% of patients with stage 2, 71% with stage 3, and 93% with stage 4/5 CKD, whereas FGF-23 values were elevated in 81% of all patients, regardless of CKD stage. Bone turnover was normal in all patients with stage 2, but was increased in 13% with stage 3 and 29% with stage 4/5 CKD. Defective mineralization was present in 29% of patients with stage 2, 42% with stage 3, and 79% with stage 4/5 CKD. Defective skeletal mineralization was associated with lower serum calcium levels and increased parathyroid hormone concentrations.
  
  
  CONCLUSIONS
  Elevated circulating FGF-23 levels and defects in skeletal mineralization early in the course of CKD suggest that factors other than the traditional markers of mineral deficiency play a crucial role in the development of renal bone disease.
authors: Department of Pediatrics, David Geffen School of Medicine at UCLA, A2-383 MDCC, 650 Charles Young Drive, Los Angeles, CA 90095, USA. kwesseling@mednet.ucla.edu
authors: Katherine
authors: K
authors: Wesseling-Perry
authors: Renata C
authors: RC
authors: Pereira
authors: Chi-Hong
authors: CH
authors: Tseng
authors: Robert
authors: R
authors: Elashoff
authors: Joshua J
authors: JJ
authors: Zaritsky
authors: Ora
authors: O
authors: Yadin
authors: Shobha
authors: S
authors: Sahney
authors: Barbara
authors: B
authors: Gales
authors: Harald
authors: H
authors: Jüppner
authors: Isidro B
authors: IB
authors: Salusky
mesh_terms: D000293:Adolescent; D000328:Adult; D016723:Bone Remodeling; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D012080:Chronic Kidney Disease-Mineral and Bone Disorder / Q000209:etiology*; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood; D006801:Humans; D007674:Kidney Diseases / Q000150:complications* / Q000378:metabolism; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood
chemical_list: C000717427:FGF23 protein, human; D010281:Parathyroid Hormone; D014807:Vitamin D; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23; C104450:25-hydroxyvitamin D