Biomaterial Database

Role of 1,25-dihydroxyvitamin D production in idiopathic hypercalciuria. 1991

L Veenhuizen, and R A Donckerwolcke

Department of Pediatrics, University of Utrecht, Wilhelmina Children's Hospital, The Netherlands.

In 9 children with idiopathic hypercalciuria, an oral calcium-loading test was performed. After this calcium excretion, vitamin D levels, parathyroid hormone levels and phosphate excretion were measured during a period of calcium restriction, a period of high calcium intake and a period of low calcium intake and phosphate supplementation. In our patients, there was no correlation between calcium excretion following acute and long-term calcium loading. Phosphate excretion was normal during the periods of low and high calcium intake and there were no signs of renal phosphate leakage. Elevated levels of 1,25-dihydroxyvitamin D were found with no significant change after altering phosphate or calcium intake (95% confidence intervals for the difference in 1,25-dihydroxyvitamin D levels were -2.2-15.4 pg/ml in the period with low and high calcium intake; -19.8-28.2 pg/ml in the period with low calcium intake and extra phosphate, and -24.2-19.6 pg/ml in the period with high calcium intake and extra phosphate). These data support the hypothesis of an autonomously elevated 1,25-dihydroxyvitamin D level as pathogenetic mechanism for idiopathic hypercalciuria.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D010710	Phosphates	Inorganic salts of phosphoric acid.	Inorganic Phosphate,Phosphates, Inorganic,Inorganic Phosphates,Orthophosphate,Phosphate,Phosphate, Inorganic
D002117	Calcitriol	The physiologically active form of vitamin D. It is formed primarily in the kidney by enzymatic hydroxylation of 25-hydroxycholecalciferol (CALCIFEDIOL). Its production is stimulated by low blood calcium levels and parathyroid hormone. Calcitriol increases intestinal absorption of calcium and phosphorus, and in concert with parathyroid hormone increases bone resorption.	1 alpha,25-Dihydroxycholecalciferol,1 alpha,25-Dihydroxyvitamin D3,1, 25-(OH)2D3,1,25(OH)2D3,1,25-Dihydroxycholecalciferol,1,25-Dihydroxyvitamin D3,1 alpha, 25-dihydroxy-20-epi-Vitamin D3,1,25(OH)2-20epi-D3,1,25-dihydroxy-20-epi-Vitamin D3,20-epi-1alpha,25-dihydroxycholecaliferol,Bocatriol,Calcijex,Calcitriol KyraMed,Calcitriol-Nefro,Decostriol,MC-1288,MC1288,Osteotriol,Renatriol,Rocaltrol,Silkis,Sitriol,Soltriol,Tirocal,1 alpha,25 Dihydroxyvitamin D3,1,25 Dihydroxycholecalciferol,1,25 Dihydroxyvitamin D3,1,25 dihydroxy 20 epi Vitamin D3,Calcitriol Nefro,D3, 1 alpha,25-Dihydroxyvitamin,D3, 1,25-Dihydroxyvitamin,D3, 1,25-dihydroxy-20-epi-Vitamin,KyraMed, Calcitriol,MC 1288
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002136	Calcium, Dietary	Calcium compounds in DIETARY SUPPLEMENTS or in food that supply the body with calcium.	Dietary Calcium
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D002675	Child, Preschool	A child between the ages of 2 and 5.	Children, Preschool,Preschool Child,Preschool Children
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293	Adolescent	A person 13 to 18 years of age.	Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths