Emerging Issues

Countries on the cutting edge of filtration

(as of Dec. 2000)

It has been over 2 years since the industrialized nations began recognizing the benefits of routine leukocyte filtration and began adopting it as a standard of practice.Globally, 10 countries have now mandated this standard of care.Canada was the first country to move to 100% leukocyte reduction.This year, Germany became the ninth European nation to date to mandate universal leukocyte reduction as a matter of public policy.Meanwhile, other countries are progressing towards leukocyte reduction without a government mandate.In the United States, progress continues with Rhode Island becoming the first state to provide 100% leukocyte reduced blood products for its health care system.

Below is an alphabetical listing of those countries that have made the commitment to universal leukocyte reduction.



Austria collects approximately 440,000 units of whole blood annually.During 1996, the Austrian Red Cross decided to introduce leukocyte reduction on clinical grounds.The blood center in Vienna, which processes 240,000 whole blood units annually, leukocyte reduces all blood by filtration.The Austrian Red Cross is now introducing leukocyte reduction by filtration into other Austrian blood banks.


In Canada, the Canadian Blood Services (CBS) and Hema-Quebec have completed their introduction of pre-storage leukoreduction for all blood products.In 1998, following a directive issued by the Canadian Government, Canada was one of the first countries in the world to implement filtering of all platelets for transfusion.


France committed to 100% leukocyte reduction in April 1998, both on clinical grounds and as a precautionary tool ensuring the safety of its blood supply.


Germany has mandated routine filtration of all blood products.The Paul-Ehrlich-Institut announced its intention to make routine blood filtration mandatory last March as an added margin of safety.According to the legal notice published in the German “Bundesanzeiger”, on September 14, 2000, the decision to require blood filtration was based on clinical studies demonstrating the benefits of removing donor white blood cells from transfusion products, The new law goes into effect on October 1, 2001.


Ireland announced plans to move to 100% leukocyte reduction in April 1998 as a precautionary measure against nvCJD.At that time the Medical Director of Ireland's National Blood Service, Dr. William Murphy, stated that the decision was based on the findings of experiments involving scrapie.Scrapie is a form of disease, transmissible spongiform encephalopathy, similar to nvCJD that occurs in sheep and goats.Since that time Eire has successfully implemented 100% leukocyte reduction of its transfused red cells and plasma.


In Malta, the Maltese Department of Health announced its intent to review the policy of 100% leukocyte reduction.Malta currently performs 18,000 transfusions annually.


New Zealand has a 2-phase approach to its government mandated universal leukocyte reduction plan.The Phase 1 target is 100% filtration of platelets by Christmas, 2000.The Phase 2 target is for 100% blood bank filtered red blood cells by April, 2001.


Portugal introduced filtration of all donated blood and platelets in early 1999 to reduce the risk of infection with nvCJD.Blood banks are using leukocyte reduction filters to extract white blood cells in order to reduce the potential risk of infection with nvCJD.


United Arab Emirates (UAE) is a federation composed of seven emirates:Abu Dhabi, Dubai, Sharjah, Ajman, Umm al-Qaiwain, Ras al-Khaimah and Fujairah.The UAE has issued a tender which will allow it to move to 100% filtered collections by July 2001.


During 1999, the United Kingdom (England, Northern Ireland, Scotland, Wales) introduced filtration of all of its blood components for transfusion, red cells, platelets and plasma.This was a move to minimize the risk of nvCJD and in response to the fact that the British government had been advised by the U.K.’s Spongiform Encephalopathy Advisory Committee (SEAC), to leukoreduce blood intended for transfusion as a precautionary measure.The U.K. government accepted SEAC’s advice, commissioned a risk assessment, and instructed the National Blood Authority (NBA) to leukocyte reduce all transfused blood products to reduce the risk of transfusion complications potentially caused by contaminants carried by the leukocytes.


In the United States, where about 13-14 million units of blood are collected annually, only about 60 to 70% of platelet components and 20% of red cells are leukocyte reduced.On September 18, 1998 the Food and Drug Administration’s Blood Products Advisory Committee (BPAC) approved a recommendation that "the benefit to risk ratio associated with leukoreduction is sufficiently great to justify routine leukoreduction of all non leukocyte transfusion blood components…” As of November 2000, the American Red Cross that manages about 45% of the US blood supply was leukocyte reducing 70%.Currently, there is no national policy on leukocyte reduction in the United States.


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New variant Creutzfeldt Jakob Disease (nvCJD)

Bovine spongiform encephalopathy (BSE, mad cow disease) is a fatal nervous system disease that was first identified in beef cattle in the U.K. in 1986.It is thought that cows were infected by being fed the remains of sheep infected with scrapie, a disease with many similarities to BSE.The causative agent in BSE is a prion.Prions can distort the normal proteins in brain and nerve cells, turning them into disease carriers as well.Similiar prions that cause BSE are thought to be responsible for Creutzfeldt-Jakob (CJD), a transmissable spongiform encephalopathy (TSE) in humans that was identified in the 1920’s.

In the last few years a new variation of CJD (nvCJD) has been documented in humans.It is thought that eating BSE infected beef caused this human transmission.Since there is a long incubation period, and no test for TSE in blood, infected people may be donating blood.Unlike the classic CJD, nvCJD infects the tonsils, spleen and lymph node.These tissues are loaded with white cells that may carry the disease in humans.In addition, studies in mice have shown that blood cells may transport these prions, especially B-lymphocytes.

In the U.K. where over 40 cases of nvCJD have been documented, the government has taken action to reduce the theoretical risk to the blood supply by requiring that all blood donations be leukoreduced.Frank Dobson, the Secretary of State for Health, said:"Although the risks are still theoretical, it is better to be safe than sorry."


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用語集

    Alloantibody
    A type of antibody directed against substances recognized as foreign to the host.

    Allogeneic Blood
    Blood donated by someone other than the patient for use in a blood transfusion.

    Alloimmunization
    The process whereby antibodies are formed which are directed towards antigens from other people, including leukocytes.It is one of the most serious transfusion complications.

    Antigens
    A substance that when introduced in the body stimulates the production of an antibody.

    Autologous Blood
    Blood that a patient donates for his own use in a blood transfusion.

    血液
    The fluid which circulates throughout the body carrying nourishment and oxygen to the cells and tissue, and at the same time takes away waste matters and carbon dioxide.

    Creutzfeldt-Jakob Disease (CJD)
    A disease that creates a protein plaque on the brain and eventually leads to death.It usually occurs in patients over the age of 60. (see nvCJD)

    Cytomegalovirus (CMV)
    A virus that resides in leukocytes.In certain patient populations, CMV infection can cause fever, hepatitis, pneumonia, and severe brain damage and can ultimately lead to death.In North America, fifty percent or more of the adult population has been exposed to the virus, making transfusion-transmitted CMV a high risk.

    Dilution Coagulopathy
    A reduction in the body’s ability to clot due to the dilution of clotting proteins

    Febrile Non-Hemolytic Transfusion Reactions (FNHTR)
    A transfusion complication defined as a rise in temperature by one degree Celsius or more during or within 24 hours of the completion of a blood transfusion.

    Graft-vs-Host Disease
    A disease caused by the infusion or transplantation of immune cells from one individual into another.

    HLA
    The tissue typing determinants used to determine compatibility.

    Hypercalcemia
    An excess of calcium in the blood.

    Hypocalcemia
    A deficiency of calcium in the blood.

    Hypothermia
    A condition of characterized by low body temperature.

    Leukocytes
    The body’s own white blood cells or leukocytes (lou-ko-cites) (WBC’s) fight disease and maintain immune function in the blood.In general, white blood cells in a blood transfusion serve no purpose, but are transfused along with the red blood cells, platelets or plasma.These unnecessary passengers can carry viruses, immune suppress patients and release toxic substances.

    Leukocyte Reduction Blood Filters
    Medical devices that remove leukocytes from either platelet or red cell transfusions.

    Neonatal Isoimmune Thrombocytopenia
    An alloimmune disorder characterized by low platelets at birth which can be accompanied by severe bleeding.

    New variant Creutzfeldt-Jakob Disease (nvCJD)
    A new variation of CJD that initally presents itself with psychiatric symptoms at a much younger age, on average 28 years old, than traditional CJD.The disease always leads to death and runs its course in about 18 months.

    Platelets (PLTs)
    PLTs are small, colorless cell fragments in your blood whose main function, along with clotting factors, is to stop bleeding.

    Platelet Transfusion Refractoriness
    The inability of platelet transfusions to adequately increase the platelet count.

    Plasma
    Plasma is the liquid portion of the blood.Plasma transports water and nutrients to the body’s tissues.Plasma also contains many proteins that help the blood to clot and fight disease.

    Purpura
    Bruising associated with receiving a blood transfusion (may occur on the skin or mucous membranes).

    Red Blood Cells (RBC’s)
    RBC’s are the cells that give the blood its red color.RBC’s carry oxygen from the lungs to the body’s tissue and take carbon dioxide back to the lungs to be exhaled.

    Scrapie
    Scrapie is a form of disease, transmissible spongiform encephalopathy, similar to nvCJD that occurs in sheep and goats.

    White Blood Cells (WBC’s)
    See leukocytes.


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