"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). Vitamin D requests at a tertiary hospital in South Africa over 2 years were retrospectively analysed along with calcium and PTH levels," scientists writing in the Journal of Clinical Pathology report (see also Hormones).
"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. Hypovitaminosis D may co-exist with a blunted PTH response," wrote D. Haarburger and colleagues, University of Cape Town.
The researchers concluded: "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.."
Haarburger and colleagues published their study in the Journal of Clinical Pathology (Relationship between vitamin D, calcium and parathyroid hormone in Cape Town. Journal of Clinical Pathology, 2009;62(6):567-569).
Additional information can be obtained by contacting T.S. Pillay, University of Cape Town, Division Chemical Pathology, Private Bag X3, Cape Town, South Africa.
The publisher of the Journal of Clinical Pathology can be contacted at: B M J Publishing Group, British Med Association House, Tavistock Square, London WC1H 9JR, England.
Keywords: South Africa, Cape Town, Clinical Pathology, Hormones, Vitamin D Deficiency, University of Cape Town.
This article was prepared by Hospital Business Week editors from staff and other reports. Copyright 2009, Hospital Business Week via NewsRx.com.
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