By: Harlan Spector / Plain Dealer Reporter
Published: Friday, June 20, 2008

A year after blood banks eliminated the most likely source of a rare but sometimes fatal lung injury in patients who receive transfusions, cases continue to be reported, leaving doctors stumped.

The American Red Cross last year stopped using women's plasma for transfusions, after the adverse reactions were linked to antibodies carried by women who have been pregnant. The antibodies, or immune cells, clash with white blood cells of some plasma recipients.

But even after the switch to all-male plasma, at least five cases of the lung injuries have been reported to the Red Cross Northern Ohio region this year. None of the cases were fatal, a Red Cross official said.

"I don't think we can say for sure we've identified all potential antibodies" that cause the reaction, said Dr. Timothy Beddow, head of the blood bank at MetroHealth Medical Center in Cleveland. "I think there are more out there."

The complication is called Transfusion Related Acute Lung Injury (TRALI). The Red Cross says it occurs in about one in 5,000 transfusions, causing acute shortness of breath as fluid fills the lungs.

Most patients recover on their own, usually within 24 hours, said Dr. Harish Kakarala, a critical care specialist at Akron General Medical Center.

But the reaction is the leading cause of transfusion-related deaths. It was linked to 35 fatalities reported to the Food and Drug Administration in 2006, the most recent yearly total available.

Most of the deaths were associated with fresh-frozen plasma, a watery derivative of whole blood that is used routinely to help clotting.

Cracking the medical mystery is complicated:

Doctors are not only uncertain about other antibodies that may be at play, but also whether there are unrelated causes. "There could be another mechanism by which TRALI occurs that may not involve antibodies," said Dr. Darrell Triulzi of the University of Pittsburgh.

The disorder can be hard to discern from other medical complications in patients who are very sick. Though TRALI death reports have increased (perhaps due to better
recognition), TRALI is not always identified or reported.

The antibodies implicated in TRALI are associated mostly with plasma, but they can also be present in other blood products, particularly platelets. Screenings for HIV and other diseases have greatly improved safety of donated blood products, but as of yet there is no universal screening for white cell antibodies.

National data on TRALI is lacking. A nonprofit group called AABB, formerly known as the American Association of Blood Banks, is working with the U.S. Centers for Disease Control and Prevention on a national reporting program, said Triulzi, who is on the AABB board.

An all-male plasma policy in the United Kingdom resulted in a sharp decline in TRALI cases, but the impact here is unknown, Triulzi said.

The Red Cross tracks cases from member hospitals, but the organization said it would be premature to release results following the all-male plasma policy.

Local spokeswoman Karen Kelley said women are still encouraged to donate whole blood and blood products. Plasma from women is needed for use in drug and vaccine production.

The local Red Cross is working on a campaign to recruit male plasma donors, Kelley said, while experts try to sniff out the causes of TRALI.

"There are three or four theories about what's going on," said Kakarala of Akron General. "The rule of thumb is if you have more than three theories, you have no idea what's causing it."

To reach this Plain Dealer reporter:
hspector@plaind.com, 216-999-4543