title: Vitamin D status and bone density in steroid-treated children with glomerulopathies: effect of cholecalciferol and calcium supplementation.
abstract: OBJECTIVE
  The aim of this study was to assess vitamin D status and bone density in steroid-treated children with glomerulopathies and to evaluate the effect of prophylactic vitamin D and calcium supplementation.
  
  
  METHODS
  Retrospective analysis was performed on 55 children aged 4-18 yrs with glomerulopathies. The following data were analyzed: antropometrical parameters, bone densitometries, parathormone, 25-hydroxyvitamin D (25-OHD), urinary calcium excretion and medications received for prevention of low bone mass.
  
  
  RESULTS
  A significant number of children (38%) had decreased spinal bone mineral density (BMD z-score < -2.0) and the majority of them (89%) had hypovitaminosis D (25-OHD < 30 ng/ml), 75% were vitamin D insufficient (25-OHD < 20 ng/ml) and 16% were vitamin D deficient (25-OHD < 10 ng/ml). The mean serum 25-OHD concentration was comparable to that of controls (19.32 ± 12.87 vs. 15.05 ± 8.52 ng/ml). Nearly all patients (82%) were receiving preparations of calcium and/or vitamin D to improve bone health. Patients on cholecalciferol had higher mean concentration of 25-OHD compared to those who were not receiving it (p=0.027) and to the controls (p=0.047). In 23 children on vitamin D and calcium supplementation for an average 6-month time, we observed an increase in the mean BMD values (p=0.004), however, mean BMD z-score and 25-OHD concentrations did not significantly change over time.
  
  
  CONCLUSIONS
  Vitamin D and bone density deficits are remarkably common in steroid-treated children with glomerulopathies, despite vitamin D and calcium repletion. In order to enhance the effectiveness of vitamin D supplementation for improvement of bone density, we suggest regular assessment of serum concentration of 25-OHD that can guide subsequent dose adjustment of vitamin D.
authors.affiliation: Department of Pediatrics, Nephrology and Toxicology, District Children's Hospital, Szczecin, Poland. mzaniew@wp.pl
authors.forename: M
authors.initials: M
authors.lastname: Zaniew
authors.forename: T
authors.initials: T
authors.lastname: Jarmoliński
mesh_terms: D000293:Adolescent; D015519:Bone Density / Q000187:drug effects*; D002118:Calcium / Q000627:therapeutic use*; D002762:Cholecalciferol / Q000627:therapeutic use*; D019587:Dietary Supplements; D005260:Female; D005921:Glomerulonephritis / Q000097:blood* / Q000188:drug therapy; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood*
chemical_list: D014807:Vitamin D; D002762:Cholecalciferol; C104450:25-hydroxyvitamin D; D002118:Calcium