Abstract
Summary: The present method for the measurement of 24,25-dihydroxyvitamin D (24,25–(OH)2D) in serum associates the highly sensitive competitive protein binding assay of Preece et al. and a double-step chromatography of the serum lipid extract (Sephadex LH 20 column and high pressure liquid chromatograph). With this assay, values observed in 16 normal children, 10 adolescents and 5 neonates, were not significantly different from those found in 14 normal adults (25–(OH)D: 20 ± 7.4 ng/ml, 24,25–(OH)2D: 1.4 ± 0.8 ng/ml). No correlation was found between 25–(OH)D and 24,25–(OH)2D serum concentrations. Measurements of 2S-(OH)D and 24,25–(OH)2D serum concentrations in some pathologic states demonstrated the existence of a 25–(OH)D-24-hydroxylase in children with three types of vitamin D resistant rickets (hereditary hypophosphatemia, pseudodeficiency rickets, and vitamin D resistance associated with Recklinghausen's neurofibromatosis). Finally, results observed during vitamin D administration suggest a regulation of the 24,25–(OH)2D concentration in human serum: 1) 24,25–(OH)2D serum concentration increased after vitamin D administration, yet it was not found higher in a 3-wk-old child with vitamin D2 intoxication (25–(OH)D: 900 ng/ml, 24,25–(OH)2D: 6 ng/ml) than in three children with vitamin D deficiency rickets in the 2nd wk after administration of vitamin D2 and calcium (25–(OH)D: 25.5 ± 9.2 ng/ml, 24,25–(OH)2D: 13.4 ± 3.7 ng/ml; 2) In a child with pseudodeficiency rickets, 24,25–(OH)2D concentrations were found elevated before treatment. They decreased to normal values during treatment with la-(OH) cholecalciferol, whereas 25–(OH)D concentrations were not significantly different before and after treatment.
Speculation: Development of methods for the measurement of 24,25–(OH)2D concentration in serum should provide valuable informations for a better understanding of vitamin D metabolism in physiologic and pathologic states in children.
Similar content being viewed by others
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Nguyen, T., Guillozo, H., Garabedian, M. et al. Serum Concentration of 24, 25-Dihydroxyvitamin D in Normal Children and in Children with Rickets. Pediatr Res 13, 973–976 (1979). https://doi.org/10.1203/00006450-197909000-00004
Issue Date:
DOI: https://doi.org/10.1203/00006450-197909000-00004
Keywords
This article is cited by
-
Preferential accumulation in vivo of 24R,25-dihydroxyvitamin D3 in growth plate cartilage of rats
Endocrine (1996)
-
1,25 Dihydroxyvitamin D3 is required for growth-independent expression of alkaline phosphatase in cultured rat osteoblasts
Calcified Tissue International (1985)
-
Changes in plasma 1,25 and 24,25-dihydroxyvitamin D after renal transplantation in children
Kidney International (1981)