title: Rickets with alopecia: an inborn error of vitamin D metabolism.
abstract: Rickets with alopecia, an inborn error of vitamin D metabolism, is described in two sisters. The rachitic disorder began during the first year of life and was refractory to 50,000 IU of vitamin D2/day. Surprisingly, both children had marked elevations in serum concentrations of 1,25-(OH)2D. Although the molecular basis for this disorder is not evident to date, intestinal end-organ unresponsiveness to exceedingly high levels of 1,25-(OH)2D was present, in addition to hyporesponsiveness of bone to these high levels of the hormone, since normocalcemia was maintained despite elevated serum levels of PTH. Therapy with oral 1,25-(OH)2D3 failed to reverse the disorder, but oral phosphorus supplements resulted in significant radiographic and clinical improvement.
mesh_terms: D000505:Alopecia / Q000150:complications* / Q000235:genetics / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D004100:Dihydroxycholecalciferols / Q000097:blood / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007015:Hypophosphatemia, Familial / Q000150:complications* / Q000235:genetics / Q000378:metabolism; D008661:Metabolism, Inborn Errors / Q000150:complications* / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D010758:Phosphorus / Q000378:metabolism / Q000627:therapeutic use; D014807:Vitamin D / Q000378:metabolism*
chemical_list: D004100:Dihydroxycholecalciferols; D014807:Vitamin D; D010758:Phosphorus; D002118:Calcium