Please use this identifier to cite or link to this item: https://hdl.handle.net/2440/53156
Citations
Scopus Web of Science® Altmetric
?
?
Full metadata record
DC FieldValueLanguage
dc.contributor.authorNeed, A.en
dc.contributor.authorO'Loughlin, P.en
dc.contributor.authorMorris, H.en
dc.contributor.authorCoates, P.en
dc.contributor.authorHorowitz, M.en
dc.contributor.authorNordin, B.en
dc.date.issued2008en
dc.identifier.citationJournal of Bone and Mineral Research, 2008; 23(11):1859-1863en
dc.identifier.issn0884-0431en
dc.identifier.issn1523-4681en
dc.identifier.urihttp://hdl.handle.net/2440/53156-
dc.description.abstractContrary to frequent claims, vitamin D insufficiency does not generally cause malabsorption of calcium because serum 1,25(OH)(2)D, which is the major determinant of calcium absorption, is maintained by secondary hyperparathyroidism. Nevertheless, because malabsorption of calcium has been described in osteomalacia, there must be a 25(OH)D level below which the serum 1,25(OH)(2)D can no longer be sustained, although it has never been defined. This paper seeks to define it. We examined the records of 3661 patients and found 319 with a serum 25(OH)D < or = 40 nM, in whom calcium absorption, serum calcium, PTH, bone markers, and vitamin D metabolites had been measured. They were grouped according to their serum 25(OH)D into four categories, 0-10, 11-20, 21-30, and 31-40 nM, and differences between the groups were tested by ANOVA. Correlations between the variables were also examined. Serum calcium, 1,25(OH)(2)D, and calcium absorption were significantly decreased and serum PTH and alkaline phosphatase (ALP) and urine hydroxyproline were increased in those with 25(OH)D < or = 10 nM. Serum ALP and urine hydroxyproline were more strongly related, inversely, to calcium absorption than to the vitamin D metabolites. We conclude that vitamin D deficiency does not reduce serum 1,25(OH)(2)D, and therefore calcium absorption, until the serum 25(OH)D falls to approximately 10 nM. At this level, the substrate concentration seems to be insufficient to maintain the level of the dihydroxy metabolite despite secondary hyperparathyroidism. Further studies are needed to see how these changes correlate with the histological changes of osteomalacia.en
dc.description.statementofresponsibilityAllan G. Need, Peter D. O’Loughlin, Howard A. Morris, Penelope S. Coates, Michael Horowitz, B.E. Christopher Nordinen
dc.language.isoenen
dc.publisherAmer Soc Bone & Mineral Resen
dc.subjectvitamin D; 1; 25(OH)₂D; 25(OH)D; vitamin D deficiency; PTHen
dc.titleVitamin D Metabolites and Calcium Absorption in Severe Vitamin D Deficiencyen
dc.typeJournal articleen
dc.identifier.doi10.1359/JBMR.080607en
pubs.publication-statusPublisheden
dc.identifier.orcidMorris, H. [0000-0002-2745-3750]en
dc.identifier.orcidHorowitz, M. [0000-0002-0942-0306]en
Appears in Collections:Pathology publications

Files in This Item:
There are no files associated with this item.


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.