Tuesday, May 3, 2011

Why HIV advance is not a universal cure

The internet is buzzing about an HIV-infected man who may have gotten rid of his disease through a bone marrow transplant. But the procedures he went through do not represent a cure for all HIV/AIDS patients, as they are risky and not proven to work in everyone. Also, the disease could still be lurking the patient's body, doctors say.

The news about Timothy Ray Brown, a 44-year-old American living in Berlin, first surfaced in 2008, when his doctors reported about his case. Here's what happened with Brown, who is HIV positive and broke his silence in a recent article with the German magazine Stern . He is battling a cancer called acute myeloid leukemia. Doctors first treated him high-dose chemotherapy, but when that failed, turned to a bone marrow transplant (which contains stem cells) in 2007.

Brown's oncologist decided to look for a bone marrow donor who had a had a special genetic mutation that made the stem cells in it naturally resistant to HIV infection. His physician, Dr. Gero Huetter, was able to find this rare match and Brown got the bone marrow transplant. He needed a second stem cell transplant because the cancer came back.

Today, he appears to be cancer free and doctors can't find traces of the virus that causes AIDS either.

This fascinating scientific advance is by no means a cure for the more than 33 million people living with HIV worldwide. As CNN's Miriam Falco reported in 2008:

1. Even though their tests do not show a presence of HIV in his system, doesn't mean it's not there. This virus is known for hiding well and popping up later. It's been seen before in patients taking anti-retroviral drugs. It is possible that if more sophisticated tests were used on this patient, they would detect the virus that is still in his body. So it's still not entirely clear that he is HIV-free.

2. The chances of finding a bone marrow donor with two copies of this genetic mutation for every one of the 33 million people worldwide living with HIV or AIDS is not realistic because only one percent of Caucasians and zero percent of African Americans or Asians have this particular genetic mutation.

3. Bone marrow transplants are dangerous for patients. Before they can get the donated stem cells that will replace their own, they have to take strong chemotherapy to destroy their own bone marrow – leaving them without an immune system to fight off any disease – until the transplanted bone marrow can make new blood cells. Plus patients run the risk of rejecting the new cells, which means they have to take immune-suppressing drugs for the rest of their life.

4. Bone marrow transplants are very expensive and not an option for many people living with this disease around the world.

No comments:

Post a Comment