A three-year-old boy with vitamin D-dependent rickets had not been well controlled until administration of 1α-OH-D3 instead of ergocalciferol (VD2). 1α-OH-D3 was more effective and more safely used than VD2, because of less accumulation into the body than VD2.
By three cases of vitamin D-resistant rickets, administration of 1α-OH-D3 improved radiological findings preceding the changes of calcium and inorganic phosphorous levels in blood serum. High dose of 1α-OH-D3 (6-16μg/day) has been used to improve the chemical data in blood serum, especially the regulation of low serum inorganic phosphorous was difficult, because vitamin D-resistant rickets have disorder of phosphate metabolism independent to vitamin D.
