Plasma products - Adverse reactions to plasma components

Plasma components can save lives, but their use isn't without risk. In some cases there can be adverse reactions, which can differ in severity.

Adverse reactions that you could experience after having a plasma transfusion include:

• a slight rise in temperature
• itching and sometimes a rash (hives) – this can occur within a few minutes of starting a plasma transfusion, but can usually be cured by slowing down the rate of transfusion or by taking an antihistamine (medication to treat mild allergic reactions)
• anaphylaxis – a rare but life-threatening allergic reaction

The risk of developing an infection after receiving plasma is very small. All blood donations used to make plasma are carefully screened for viruses to make sure they're safe.

However, as is the case with most medical procedures, there are possible risks associated with receiving plasma. Some of these are outlined below.

Transfusion-related acute lung injury (TRALI)

Transfusion-related acute lung injury (TRALI) is a reaction that can occasionally occur in someone who receives a plasma transfusion. During or shortly after the transfusion the person will have breathing difficulties, which can sometimes be severe.

The reaction is thought to occur because the donated plasma contains antibodies (proteins produced by the donor's immune system), called HLA antibodies, that react with your white blood cells.

This occurs more often when plasma has been donated by a female donor who's had pregnancies in the past and whose immune system produced the antibodies as a response to pregnancy.

Antibodies are usually produced by the immune system to fight organisms in the blood that the body regards as "foreign", such as bacteria. However, in pregnancy they have a protective role.

To minimise the risk of TRALI, plasma from male donors is usually used to make fresh frozen plasma and other plasma-containing blood components and products used for transfusion.

Fractionated plasma products don't cause TRALI.

Variant Creutzfeldt-Jakob disease (vCJD)

Variant Creutzfeldt-Jakob disease (vCJD) is the human form of bovine spongiform encephalopathy (BSE), commonly known as mad cow disease.

First identified in 1996, vCJD is a rare neurological illness that causes brain damage. It occurs as a result of eating the meat of cattle infected with BSE.

The risk of developing vCJD after having a blood transfusion is very small, but there's currently no test available to screen donated blood for the prion protein that causes vCJD.

Each year in England, approximately 2 million units of blood are transfused. To date, there have only been a few cases where patients are known to have become infected with vCJD after having a blood transfusion.

However, to minimise the risk further, the NHS has put a number of precautions in place. These include:

• removing all white cells by filtering cellular blood components (red blood cells and platelets)
• importing fresh frozen plasma from countries where there have been no cases of vCJD for transfusion to those born on or after January 1 1996
• using pooled plasma for fractionation from countries where there have been no cases of vCJD, and using recombinant clotting factors (produced in a laboratory using DNA technology) for treating people with haemophilia, where these products are available
• only using plasma transfusions when absolutely necessary

Read more about Creutzfeldt-Jakob disease (CJD).