title: Plasma concentrations of vitamin D metabolites in a case of rickets of prematurity.
abstract: Rickets was diagnosed in an extremely low-birthweight infant 16 weeks after birth. She had a normal plasma concentration of 25-hydroxyvitamin D, a relatively low level of 24,25-dihydroxyvitamin D, and a markedly elevated 1,25-dihydroxyvitamin D level compared with adult standards. The plasma concentrations of the vitamin D metabolites were, however, indistinguishable from those of healthy preterm infants who received a similar diet of human milk and vitamins. The results indicate that rickets was not caused by vitamin D deficiency or by abnormal vitamin D metabolism, but by calcium and/or phosphate deficiency, and that the calcium and phosphorous content of human milk may be inappropriately low for very low-birthweight infants.
mesh_terms: D015650:24,25-Dihydroxyvitamin D 3; D015652:25-Hydroxyvitamin D 2; D000469:Alkaline Phosphatase / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000097:blood; D004100:Dihydroxycholecalciferols / Q000097:blood*; D004872:Ergocalciferols / Q000031:analogs & derivatives / Q000097:blood; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000097:blood*; D008895:Milk, Human; D010758:Phosphorus / Q000097:blood; D012279:Rickets / Q000097:blood*
chemical_list: D004100:Dihydroxycholecalciferols; D004872:Ergocalciferols; D015652:25-Hydroxyvitamin D 2; D010758:Phosphorus; D015650:24,25-Dihydroxyvitamin D 3; D000469:Alkaline Phosphatase; D002117:Calcitriol; D002118:Calcium