@article{hbkup:/content/journals/10.5339/qmj.2009.1.21, author = "Al Hemaidi, N. and Soliman, A.", title = "A Thalassemic Adolescent Presented With Bone Pain, Tetanic Contractions and Growth delay: Combined vitamin D and Parathyroid defects", journal= "Qatar Medical Journal", year = "2009", volume = "2009", number = "1", pages = "", doi = "https://doi.org/10.5339/qmj.2009.1.21", url = "https://www.qscience.com/content/journals/10.5339/qmj.2009.1.21", publisher = "Hamad bin Khalifa University Press (HBKU Press)", issn = "2227-0426", type = "Journal Article", keywords = "Hypoparathyroidism", keywords = "Vitamin D", keywords = "Thalassemia", eid = "21", abstract = "Parathyroid hormone (PTH) and l,25-(OH) 2 vitamin D play key roles in the regulation of calcium and phosphate balance. Circulating levels of PTH can change within seconds after an alteration in serum calcium. When the serum calcium falls PTH is rapidly released and acts quickly to promote calcium reabsorption in the distal tubule and the medullary thick ascending limb of the loop of Henley. PTH also stimulates the release of calcium from the rapidly exchangeable pool of bone calcium and a chronic elevation in serum PTH increases renal l,25-(OH) 2 vitamin D production.", }