Jan. 26, 2001 (Washington) -- Most Americans probably do not know why more than half of the nation's blood supply is filtered to remove the white blood cells, a process called leuko-reduction. But Nancy Chance, a blood-bank coordinator at a small hospital in Noblesville, Ind., can explain why the expensive filtration process is an important one for patient safety.
Several years ago, her brother-in-law's 39-year-old twin received unfiltered blood while being treated for a cancer of the bone marrow. When the body receives substances that it recognizes as foreign, the immune system is triggered to form antibodies. These antibodies can be reactivated when the body is exposed to a foreign substance on a separate occasion. In the case of her relative, antibodies were triggered against the bone marrow transplant meant to save his life, and he died a few months later.
Now a panel of experts has advised the government to require all blood to undergo leuko-reduction as soon as it is feasible. They believe the filtering process will make the nation's blood supply safer for organ transplant recipients and protect others from transfusion-related side effects, like viral infections, fevers, and chills caused by the unnecessary white blood cells.
On face value, the decision made Friday -- after two days of heated discussion -- appears to make sense. But it lacks universal support. Why?
Cost vs. Care
No one questions the benefits of leuko-reduction for at least a certain group of patients who are at a greater risk of suffering transfusion-related side effects. But there are those that say that the cost, estimated at $500 million per year, simply does not justify doing it for everyone.
Among those is Gerald Sandler, MD, director of the blood bank at Georgetown University Hospital in Washington, D.C.
He says the money would be better spent on other patient protections, and that evidence supporting its wide use is scanty. He also is fearful that adopting this universal approach now would halt vital ongoing research in this area.
People who support universal leuko-reduction, however, say that available evidence is more than adequate.
"There are ... clear benefits to universal leuko-reduction," Paul Ness, director of transfusion for John Hopkins Medical Institutions, tells WebMD. He says that in crowded wards, at-risk patients could inadvertently be given the unfiltered blood.
"If you want a reliable system, you have got to keep things simple," Ness says.
Better Product or a Worse Process
In general, most experts agree the filtered blood is a better product. But some question whether this better product will indeed lead to a better process.
For instance, the filtering process would reduce the nation's blood supply by nearly 10% at a time when further shortages are possible. They also say that the filtering process could undermine stepped-up efforts to encourage badly needed donations by minority donors.
Cleso Bianco, MD, director of the New York Blood Centers, explains that the filtering process would eliminate some donations from African-Americans because they carry a gene for sickle cell anemia, a disease in which red blood cells become abnormally shaped. While blood from sickle cell anemics cannot be used for transfusions, certain blood components -- components that are in short supply -- could still be used to treat others in the community.
"This universal leuko-reduction shouldn't go forward until the implications are understood," says Bianco, who also has served as president of America's Blood Centers, which collects about half of the nation's blood supply. "The impact on African-Americans needs to be examined."
A Divided Front
But universal leuko-reduction enjoys the support of the American Red Cross, which collects the other half of the nation's blood supply.
The issues raised by filtration are not insurmountable, and even a small benefit would justify requiring universal leuko-reduction, the organization says.
In addition, Jacquelyn Fredrick, executive vice president of the American Red Cross, argues that selective leuko-reduction essentially discriminates against at least half of patients getting blood transfusions because only half of the nation's blood supply is filtered.
"It's not an either/or issue," she tells WebMD. "If costs were off the table, I bet almost everyone would already be using leuko-reduced blood."
Leuko-reduction could save money in the long run. Use of filtered blood would lead to shorter hospital stays, according to Edward Snyder, MD, director of transfusion at Yale-New Haven Hospital. In addition, adopting universal leuko-reduction would eliminate screening blood for common blood-borne viruses, which essentially are eliminated by the filtering process, he says.
At present, the decision of when to use leuko-reduced blood is left up to individual medical institutions. The FDA does believe that the process leads to a better product. But unlike health officials in Canada and some European countries, where leuko-reduction is required, U.S. health authorities have stopped short of requiring universal filtration.
The panel's Friday decision, however, opens the door for the FDA to move ahead with a rule requiring universal use of leuko-reduced blood.