Bone density in thalassemic children during the course of the disease.

The study was carried out on 50 thalassemic children and 20 control subjects aged 5--15 years. The cortical thickness in thalassemic children was less than in control subjects. The bone loss was more obvious in girls (P less than 0.0005) than in boys (P less than 0.05). The greater bone loss in girls could not be explained by the level of blood hemoglobin because in both sexes the mean value was the same (7.3 +/- 0.5 g/dl). Of the 12 thalassemic children observed for 9--24 months, 9 showed no signficant bone change, 2 showed an improvement of cortical thickness and only 1 showed bone loss. Of the 11 thalassemic children observed for 25--48 months, 4 showed significant bone loss and 7 no change of the bone density. In both groups the mean value of pretransfusion blood Hb was 7.3 g/dl and the sex distribution was equal. A relationship was found in both control and thalassemic children between bone density and urine phosphorus to urine creatinine ratio.