Hemophilia is a bleeding disorder (deficiency of a blood clotting factor/ protein) resulting
in bleeding in joints and muscles. As patients continue to bleed into their joints they
develop progressive joint damage leading to joint contractures, disability and days missed
from work and school resulting in chronic debilitating pain and compromised quality of life.
Current therapy is the administration of the missing protein or factor concentrate on a
scheduled basis to prevent bleeding into the joints referred to as prophylaxis. This factor
concentrate is expensive ~ $ 3,000 - 6,000 per infusion/ week in a child weighing 20 kg
translating into $ 77,000 /yr for life. This regimen has been shown to be effective to
prevent joint bleeds but the timing is unclear and not based on adequate evidence. Currently
joint damage is diagnosed using MRI which is expensive and requires sedation in children < 6
yrs of age. Therefore there is a need for a user friendly tool such as a ultrasound to
monitor for the development of joint disease and tailor treatment based on an individual
child's needs. This would also enable differentiating a joint bleed from a soft tissue bleed
which present similarly and duration of treatment tends to be longer for a joint bleed.
Acharya et al have previously shown that ultrasound is comparable to MRI for the diagnosis of
hemophilic joint disease in hemophilia patients over the age of 6 years. However, the
diagnostic findings in children < 18 years with hemophilia on ultrasound is not well
The hemophilic synovium after repeated joint bleeds reveals the development of new vessels
which are fragile and contribute to recurrent joint bleeds. Acharya et al have previously
shown that angiogenesis, a process of new vessel formation is active in hemophilic synovium
and angiogenic markers were significantly elevated in hemophilic patients with joint disease
when compared to those without (2). Since ultrasound can detect these new vessel changes in
the hemophilic synovium in hemophilia patients with joint disease and hemophilia patients
with joint disease demonstrate elevated markers of new vessel formation these investigators
would now like to determine whether radiological findings of hemophilic joint disease
correlate with serological angiogenic markers. This may enable the development of biomarkers
for hemophilic joint disease.
Findings from this study will enable the development of ultrasound as a user friendly tool in
the hemophilia clinic in order to understand whether every pain and swelling in a joint is
actually a joint bleed or soft tissue bleed and to monitor for joint changes to institute or
augment scheduled factor infusions ( prophylaxis). This will also result in significant
improvement in quality of life with tailored prophylaxis .