90% Sickle Cell Patients Cured by Breakthrough TreatmentBy jayita, Gaea News Network
Thursday, December 17, 2009
Sickle cell disease is an inherited life-long blood disorder. It affects 1 in 500 black Americans, causing symptoms that include wheezing, pain, stroke and organ failure, researchers said. Red blood cells are typically smooth and disk-shaped. But in sickle-cell disease, they take the form of a crescent and clump together, causing blockages in the vessels that carry oxygen- rich blood to limbs and organs. The sickle cell disease occurs because of a mutation in the hemoglobin gene.
Sickle cell is a devastating illness that puts people in and out of hospitals their whole lives
,said Ira Bragg-Grant, executive director of the American Sickle Cell Anemia Association, in Cleveland.
While doctors have long used transplants to replace misshapen red blood cells in children, the treatment has been too toxic for adults. A study in today’s New England Journal of Medicine found that replacing only a portion of the cells can work. Recipients were sickle cell-free 30 months later.
Radiation Therapy and Transplantation
At the National Institutes, Hsieh and colleagues applied radiation for the sickle cell disease patients. To weaken the patients’ immune systems so their bodies wouldn’t reject the incoming cells, the researchers gave them Campath, a drug made by Cambridge, Massachusetts-based Genzyme Corp. It destroys certain white blood cells.
Patients receive bone marrow containing stem cells, to make healthy red blood cells, from a sibling.
Hsieh’s goal was to get a favorable mix of donor cells and recipient ones. The study’s results suggest they have the right mix, he said.
Drawback of transplantation
According to Hsieh, the main drawback of transplantation is that it is hard to find a suitable donor. In his study, he was looking for patients who had siblings with matching white blood cells. Of the 112 eligible patients whose blood type was tested during recruitment, only 24 had qualifying siblings.
Moreover, compatible donors are less found among African and American since they are unrepresented, according to Eugene Orringer, a professor of medicine at the University of North Carolina at Chapel Hill.
Risk of Transplantation
In stem-cell transplantation, the donor’s immune cells sometimes attack the organs in the patient’s body. Adults are more vulnerable to these reactions than children. The high risk of graft-versus-host disease is one reason Hsieh sought to devise a less-toxic transplant regimen.
While stem-cell transplants are curative, doctors must weigh the risk of infection or even death, said Orkin. They must also consider the amount of existing organ damage and whether it’s reversible, he said.
Highly damaged organs can complicate a transplant. On the other hand, people who have had a stroke or organ failure “have more to lose if you don’t act,” said Hsieh, the study author.
Currently adult patients with severe sickle cell disease have two treatment choices, said Stuart Orkin, a pediatrics professor at the Harvard Medical School in Boston.
- Hydroxyurea, an anti-tumor drug that is approved for treating pain in sickle cell disease. The problem with hydroxyurea, said Orkin, is that it doesn’t work in all patients. It can also cause infertility .
- Another is blood transfusions to suppress the production of sickle cells. The trouble is, some people develop iron overload that makes further transfusion impossible.
Statistical Record of sickle cell disease
Almost 75,000 people suffering sickle cell disease are hospitalized each year, with total cost of $475 million, as reported by National Center for Health Statistics, a U.S. agency. For males who inherit the sickle gene from parents, could survive maximum of 42 years, as study revealed by Harvard Medical School.
How to combat the disease
Scientists are hopeful that gene therapy will knock out the disease in near future while stressing on transplantation being the immediate solution to sickle cell disease. For more adults to be freed from the chronic disease by transplants would be a phenomenal development and we are looking forward to that.
Tags: sickle cell disease, stem cell therapy, stem cells