نقش هورمون پاراتیرویید بر قامت بیماران مبتلا به بتاتالاسمی ماژور

  The Role of Parathyroid Hormone on Stature in Major Beta-Thalassemic Patients     GR. Moshtaghi Kashanian PhD 1 , A. Ahmadi MD2, MM. Hayat Bakhsh MD3     1- Assistant professor, Dept. of Biochemistry, Faculty of Medicine, University of Medical Sciences, Kerman, Iran   2- Professor of Pediaterics, University of Medical Sciences, Kerman, Iran   3- Assistant professor of Internal Medicine, Faculty of Medicine, University of Medical Sciences, Kerman, Iran   Background: Bone changes are typical complications of thalassaemia major, with unknown pathogenesis. There are only a few studies concerning mineral metabolism and parathyroid hormone (PTH) level in the patients whit this disorder, but the number of cases are limited and results are controversial. Since there are many major beta-thalassemic patients in Kerman area, the present study investigated the related factors in bone metabolism of these patients including PTH, ionized calcium, inorganic phosphate, and alkaline phosphatase level in patients with different age.   Material and Methods: In a cross sectional study, blood samples (5ml) were collected from 200 patients refferiry to the thalassemia clinic for blood transfusion. The patients were divided into five different age groups (<2, 3-7, 8-12, 13-16 and 17-24 years), and their results were compared with the results obtained from 83 healthy subjects as control group. Furthermore, a questionnaire was filled by a physician for all the patients and the control group, which included height, weight, and clinical symptoms of calcium deficiency. For comparison of height and weight, patients were divided into 24 groups according to their age.   Results: Analysis of data showed significant decreases (p<0.001) in serum level of PTH and calcium of all the patients, while there were significant increases in the level of the inorganic phosphate of them (p<0.01). Furthermore, alkaline phosphatase was increased significantly (p<0.05) only in the children < 2 years, compared with the respective control group, while there were no significant changes among the other age groups. Symptoms of calcium deficiency such as paraesthesia were detected in 28%, muscular spasm in 7%, and seizure in 7.5% of the patients. Statistically, only one year old patients had normal height and weight, while significant decreases were detected for the other age groups (p< 0.05), which became more predominant in the older patients (p<0.001).   Conclusion : The present study indicated that the lower secretion of PTH following the deposition of iron in different tissues (89.5% of the patients had ferritin level of above 1500 ng/ml, and 91% had no regular desfral use), that causes the reduction of ionized calcium, and increase of inorganic phosphate. Furthermore, Low level of PTH leads to impaired metabolism of calcium and phosphate, and lower stature and body weight of these patients.     Key words: b -thalassaemia major, Parathyroid, Hormone Ionized calcium, Inorganic phosphate, Alkaline phosphatase, Stature, Weight     *Corresponding author Tel:(0341)3221662,Fax:(0341)3221671, E-mail: [email protected]   Journal of Rafsanjan University of Medical Sciences and Health Services, 2004, 3(4): 258-266