Filtering Blood

Imagine being able to clean blood by putting it through a filter. That’s what blood banks around the country are doing to make blood transfusions safe for patients with weak immune systems.

Donated blood is screened and tested for a common infection called cyto-megalo-virus, or CMV. Newborns who need transfusions, some AIDS patients, and most people undergoing bone marrow or solid organ transplants need CMV-free blood.

M.D.:
“CMV is a very, very common virus. Fifty-percent of otherwise healthy adults have been infected with CMV.”

With CMV-free blood in short supply around the country, attention is now focused on a new study that shows CMV can be filtered out of blood.

M.D.:
“We’re filtering out white blood cells…so that the blood coming out of the filter no longer has those white blood cells that contain the virus and it can be safely given to patients without transmitting the infection.”

The filter is pretty simple. It’s actually just a simple gel that’s inside the filter that the white blood cells stick to.

Robert, Patient, Seattle, WA:
“I sure hope it doesn’t get any worse.”

Robert had a bone marrow transplant for non-Hodgkin’s lymphoma. He could need up to 100 units of CMV-free blood in the next couple of months.

M. D.:
“They don’t have the right kind of cells to fight virus infections, therefore, if they come in contact with this virus, usually through blood products after their transplant, it can cause very serious infection and sometimes death.”

CMV poses little risk to most healthy people. People who carry the virus have had it their entire lives, even though they may never get sick. Insurance covers filtered blood and many blood banks around the country are using filtration. Doctors say there is still no way to filter out HIV or the hepatitis virus from blood.

Source: Ivanhoe