Bone Disease in Haemoglobin Disorders

Bone disease represents a prominent cause of morbidity in patients with thalassaemia and other haemoglobin disorders. The delay in sexual maturation, the presence of diabetes and hypothyroidism, the parathyroid gland dysfunction, the haemolytic anaemia, the progressive marrow expansion, the iron toxicity on osteoblasts, the iron chelators, and the deficiency of growth hormone or insulin growth factors have been identified as major causes of osteoporosis in thalassaemia. Adequate hormonal replacement, effective iron chelation, improvement of hemoglobin levels, calcium and vitamin D administration, physical activity, and smoking cessation are the main to-date measures for the management of the disease. During the last decade, novel pathogenetic data suggest that the reduced osteoblastic activity, which is believed to be the basic mechanism of bone loss in thalassemia, is accompanied by a comparable or even greater increase in bone resorption. Therefore, potent inhibitors of osteoclast activation, such as the aminobisphosphonates, arise as key drugs for the management of osteoporosis in thalassaemia patients and other haemoglobin disorders.