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Doctors at John Hopkins say Pamela Newton is the first adult worldwide to be cured of Sickle Cell Disease using an experimental bone marrow transplant.
Fifteen months ago, the pain from Pamela
Newton's sickle cell disease was excruciating.
She spent more time in the hospital than in her
Capitol Heights apartment. She was on 15 pain
pills a day, all heavy narcotics. She was
bleeding regularly and needed daily
transfusions of platelets. Today doctors at Johns
Hopkins Hospital say that Newton is one of the
first adults in the world to be cured of sickle cell
disease - and the first using an experimental
bone marrow transplant that could cure
thousands like her who have been told they will
never get better.
Word of a breakthrough gives hope to the
roughly 80,000 Americans - and millions
around the world - who suffer from this
debilitating and usually fatal disease, which is
predominant among African-Americans and
Hispanics. Bone marrow transplants have been
used to treat sickle cell disease for 20 years -
but almost all of the 200 cured have been
children. The treatments - high doses of
chemicals that knock out the patient's own
marrow before the transplant - are so toxic that
adults with sickle cell-induced organ damage
would be unlikely to survive them.
Brodsky said his team's procedure, developed
by Dr. Ephraim Fuchs and Dr. Leo Luznik, is less
toxic. They say they no longer believe they
have to destroy as much of the patient's
marrow as they once did - so they administer
just enough chemotherapy to suppress the
immune system. That dose keeps patients from
rejecting the new marrow without harming their
organs. This change allows transplants for
adults, as well as children. Because the
procedure occurs later in life, it relieves parents
of the burden of making the decision for their
youngsters (even in children, the sickle-cell
transplant mortality rate is 5 percent to 10
percent). Instead, it allows the adult patient to
see how severe the disease is before deciding
whether to have a transplant.
Another transplant obstacle has been finding
a perfect bone marrow match - a full sibling's
marrow provides the best chance. But there's
only a 25 percent chance that even a full
sibling will be a match. And since sickle cell is
inherited, siblings may also have the disease.
That leaves about a 10 percent chance that a
patient will find a suitable donor. Brodsky's
procedure requires just a half-match -
meaning that children and parents of the
patient could be suitable donors.
Three days after the transplant, the patient is
given a high dose of a drug called
cyclophosphamide. Just as the bone marrow is
taking root, the drug kills off the donor's
lymphocytes - blood cells that are part of the
immune system.
The cyclophosphamide spares the donor's stem
cells and allows them to establish new blood
cells and a new immune system. The nascent
immune system is re-trained to see the patient's
body as friend, not foe. This prevents the patient
from rejecting the transplanted bone marrow -
and prevents the newly developing immune
system from attacking the patient.
Information Source: Sickle Cell Information Centre
News Update for April 2008:
www.scinfo.org/news.htm
www.baltimoresun.com/news/health/balte.
sickle30mar30,0,6112155.story
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