About 40% of boys with hemophilia developed joint changes detectable by magnetic resonance imaging (MRI), especially in the ankles and elbows, despite dose- and frequency-adjusted prophylaxis. This is according to the serial and end-of-study findings from the Canadian Hemophilia Primary Prophylaxis Study, which were reported in Research and Practice in Thrombosis and Haemostasis.
The study also found that joint bleeding was associated with a higher risk of arthropathy on end-of-study MRIs, as well as that soft-tissue changes on interval MRIs were associated with a higher risk of osteochondral findings in end-of-study MRIs and X-rays.
These findings led the authors to conclude that serial imaging techniques such as MRI in boys with hemophilia could help guide the choice of prophylaxis on an individualized basis. This in turn could minimize joint bleeding and preserve joint health in the long term.
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The relevance of changes on MRI in severe hemophilia A was unclear thus far. To examine the importance of changes on interval MRIs in assessing structural joint outcomes in boys with severe hemophilia A who are treated prophylactically, a team of researchers led Paul Babyn, MDCM, evaluated the x-rays and mid- and end-of-study MRIs of 46 boys with hemophilia A who took part in the Canadian Hemophilia Prophylaxis Study.
The results showed that 18 of the 46 boys (39%) had osteochondral changes in at least 1 of their joints. In 27 boys, at least 1 joint showed an interval change in MRI score of at least 1 point.
Soft tissue changes such as the presence of synovial hypertrophy or hemosiderin on interval MRIs were associated with later osteochondral findings, and joint bleeding was associated with a higher risk of end-of-study MRI changes.
Stimec J, Dover S, Pullenayegum E, et al. Magnetic resonance imaging in boys with severe hemophilia A: serial and end-of-study findings from the Canadian Hemophilia Primary Prophylaxis Study. Res Pract Thromb Haemost. 2021;5(7):e12565. doi:10.1002/rth2.12565