title: Vitamin D metabolism in hypophosphatemic rickets.
abstract: Vitamin D metabolites were measured in 21 patients with hypophosphatemic osteomalacia of juvenile onset. In eight patients who had not received any antirachitic treatment, serum 25-hydroxyvitamin D(25-OH-D) and 1,25-dihydroxyvitamin D (1,25-[OH]2D) values were normal, whereas serum 24,25-dihydroxyvitamin D (24,25-[OH]2D) values were lower than in normal subjects. In 13 patients who were receiving ergocalciferol and oral elemental phosphorus, serum 25-OH-D and 24,25-(OH)2D concentrations were elevated and serum 1,25-(OH)2D values were low. The findings in untreated patients supported the hypothesis that vitamin D metabolism is abnormal in hypophosphatemic rickets/osteomalacia. The reduction of serum 1,25-(OH)2D levels with ergocalciferol and phosphate therapy gives further support to a therapeutic role for 1,25-(OH)2D in this disorder.
mesh_terms: D015650:24,25-Dihydroxyvitamin D 3; D000293:Adolescent; D000328:Adult; D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D002112:Calcifediol / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002648:Child; D002675:Child, Preschool; D004100:Dihydroxycholecalciferols / Q000097:blood; D004872:Ergocalciferols / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010018:Osteomalacia / Q000097:blood* / Q000188:drug therapy; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood*; D010758:Phosphorus / Q000627:therapeutic use; D012279:Rickets / Q000097:blood* / Q000188:drug therapy; D014807:Vitamin D / Q000097:blood*
chemical_list: D004100:Dihydroxycholecalciferols; D004872:Ergocalciferols; D010281:Parathyroid Hormone; D010710:Phosphates; D014807:Vitamin D; D010758:Phosphorus; D015650:24,25-Dihydroxyvitamin D 3; D000469:Alkaline Phosphatase; D002117:Calcitriol; D002112:Calcifediol