Relationship between vitamin D, calcium and parathyroid hormone in Cape Town
- 12 February 2009
- journal article
- research article
- Published by BMJ in Journal of Clinical Pathology
- Vol. 62 (6), 567-569
- https://doi.org/10.1136/jcp.2008.062877
Abstract
Aim: The aim of this study was to test the hypothesis that vitamin D deficiency is associated with abnormal levels of calcium and parathyroid hormone (PTH). Methods: Vitamin D requests at a tertiary hospital in South Africa over 2 years were retrospectively analysed along with calcium and PTH levels. Results: Only when the 25-hydroxyvitamin D (25(OH)D) level dropped below 25 nmol/l, was there a significant rise in PTH. A subnormal 25(OH)D level was also not always related to hypocalcaemia, as more than half of patients with their 25(OH)D level below 25 nmol/l had calcium levels in the reference range. However, all patients with calcium levels below 1.8 mmol/l were shown to have vitamin D insufficiency. Conclusion: Hypovitaminosis D may co-exist with a blunted PTH response. Therefore, assumptions about vitamin D status should not be made based on PTH and calcium values. 25(OH)D measurements should be requested when vitamin D deficiency is clinically suspected, irrespective of biochemical results.Keywords
This publication has 12 references indexed in Scilit:
- Vitamin D Reinvented: Implications for Clinical ChemistryClinical Chemistry, 2008
- Glomerular Filtration Rate Is a Major Determinant of the Relationship between 25-Hydroxyvitamin D and Parathyroid HormoneCalcified Tissue International, 2007
- Vitamin D deficiency: a global perspectiveArchives of Endocrinology and Metabolism, 2006
- The relationship between vitamin D and parathyroid hormone: calcium homeostasis, bone turnover, and bone mineral density in postmenopausal women with established osteoporosisBone, 2004
- The investigation of hypocalcaemia and ricketsArchives of Disease in Childhood, 2003
- Effects of Above Average Summer Sun Exposure on Serum 25-Hydroxyvitamin D and Calcium AbsorptionJournal of Clinical Endocrinology & Metabolism, 2002
- Vitamin D Deficiency and Secondary Hyperparathyroidism in the Elderly: Consequences for Bone Loss and Fractures and Therapeutic ImplicationsEndocrine Reviews, 2001
- Serum vitamin D concentrations among elderly people in EuropeThe Lancet, 1995
- Sunshine exposure and serum 25-hydroxyvitamin D concentrations in exclusively breast-fed infantsThe Journal of Pediatrics, 1985
- COMPETITIVE PROTEIN-BINDING RADIOASSAY FOR 25-HYDROXYCHOLECALCIFEROL1Journal of Clinical Endocrinology & Metabolism, 1971