Bone pain in thalassaemia: assessment of DEXA and MRI findings

An increasing number of adult thalassaemics have been complaining of aches and pains of varying degrees of severity. In a minority the pains are debilitating and there is stiffness in movement. This study is an attempt to understand the osteoporosis of thalassaemia using DEXA and MRI as the main investigative tools. 122 patients with homozygous beta-thalassaemia were examined by DEXA. It was found that almost half had BMD below two standard deviations from the mean for the normal population, especially in the lumbar spine. There was no marked worsening with age. However the proportion of patients who had their first transfusion after the 3rd year (especially after the 6th) was significantly greater in those with the low BMD. There is also an excess of hypogonadic thalassaemics amongst those with low BMD. 72 thalassaemics were examined by MRI of marrow. Hypercellular, dark marrow on T1 weighted images found in young patients (20-30 yr) was replaced by fatty marrow in later life (30-40 yr). In a group of 21 older thalassaemics (33-62 yr) extreme bone marrow expansion was expressed by the reappearance of hypercellular areas, giving the impression of patchiness which affects not only the diaphyses but also the metaphyses. These patients mostly (66%) had thalassaemia intermedia and had started irregular transfusion after the 6th year of life. About 75% had a BMD below 2 SD. The conclusion is that patients who were late in receiving blood and especially those with thalassaemia intermedia had a more expanded bone marrow with pressure on cortical bone which caused pain in several cases. An attempt was made in 10 patients to reduce marrow hyperplasia by using hydroxyurea. Results showed a relief of pain and modification of magnetic signal intensity.