139: Bone mass in thalassemic children

Abstract

Bone mass has been studied very little in b-thalassemic patiente By making duplicate measurements of cortical thickness on the metacarpus of both hands, it is possible to calculate the cortical thickness in each child with an error of less than 5%. Our material consists of 50 thalassemic children treated regularly by transfusions and 20 controls aged 5.15 years. We found that the cortical thickness in thalassemic children was smaller than in the controls. The bone loss was more obvious in girls (p<0.0005) than in boys (p<0.05). The pretranfusion mean value for blood Hb was during the 12 months before the estimation of cortical thickness 7.26±0.9 g/100ml for girls and 7.3±0.5g/100ml for boys. A comparison in the thalassemic children between males and females showed that the cortical thickness was smaller in females than in males (0. l<p<0.05). The greater bone loss in girls than in boys could not be explained by the level of blood Hb because in both groups the mean value was the same. Of the 12 thalassemic children observed for 9-24months, 9 showed no significant bone change, 2 an improvement of cortical thickness and only one bone loss. Of the 10 thalassemic children observed for 25-48 months, 4 showed a significant bone loss and 6 no change of the bone mass. In both groups the mean value of pretransfusion blood Hb was 7.4g/100ml and the sex distribution equal. This finding may mean that the bone loss in this age group of thalassemic children needs more than 24months to be obvious radiologically when the pretransfusion blood Hb is 7-8g/100ml.