Abstract
Treatment with 1α, 24 dihydroxy vitamin D3 (1, 24(OH)2D3) was evaluatedin a patient aged 7 years and 10 months old, who was an untreated girl with primary hypophosphatemic rickets.
After oral administration of 1, 24(OH)2D3, 1μg/day for 4 weeks, her radiographic findings was showed healing of rickets. Fasting serum P concentration was not increased, thereafter oral phosphate was started and 1, 24(OH)2D3 dosage was increased to 3μg/day. However fasting serum P concentrations showed no remarkable changes. After changing the 1, 24(OH)2D3 to the same dosage of 1α, 25 dihydroxy vitamin D3 (1, 25(OH)2D3) the radiographic findings and fasting serum P concentration showed no remarkable changes. Serum alkaline phosphatase activity decreased slightly. During both treatment the serum Ca and the urinary Ca/creatinine ratio stayed within the normal range. The serum concentrations of 1, 25(OH)2D3 were low before and during the treatment with 1, 24(OH)2D3.
Growth acceleration was 123% of that expected for change in chronological age after treatment.
It is concluded that both 1, 24(OH)2D3 and are effective in the treatment of primary hypophosphatemic rickets.
