Reduced bone mineral density in polytransfused patients with beta thalassemia, poorly defined role of hypoparathyroidism in pathogenesis

ABSTRACT

Patients with beta thalassemia frequently develop bone disease of multi-factorial etiology. We studied the prevalence of hypoparathyroidism in addition to other laboratory indices of bone and calcium metabolism [serum calcium, phosphorus and alkaline phosphatase], in fifty patients with beta thalassemia major and ten patients with beta thalassemia intermedia. These biochemical indices were correlated to bone mineral density assessed by dual x-ray absorptiometry [DEXA]. Hypoparathyroidism was found in 8% of the studied thalassemic patients with significantly lower serum parathormone and calcium and significantly higher serum phosphate compared to control subjects. Results of DEXA scan revealed decreased bone mineral density in 90% of the studied thalassemic patients. Serum parathyroid hormone showed no significant correlation with any of the studied DEXA parameters. In conclusion, bone disease is present in the majority of thalassemic patients with no significant correlation with parathyroid hormone, denoting that bone disease in beta thalassemia is likely to be multi-factorial