HLA Antibody Testing: Maintaining the Safety of Our Blood

To remain compliant with a new practice standard and continue our focus on blood safety, the Mayo Clinic Blood Donor Program has updated its screening and testing for female blood donors who have ever been pregnant

What's Changing?

We will now test for certain antibodies in donated blood. These antibodies are called human leukocyte antigen (HLA) antibodies. They are more common in the blood of people who have had a blood transfusion or those who have been pregnant. Some people may have these antibodies for other reasons as well. If testing shows you have HLA antibodies, you may only be able to donate whole blood and red blood cells. This may happen even if you have donated in the past.

Are these antibodies harmful to me?

If HLA antibodies are in your blood, they are not harmful to you. These antibodies are your body’s natural response to your baby’s blood if you’ve been pregnant. They also are a natural response to a donor’s blood if you’ve had a transfusion. However, if HLA antibodies are in the blood you donate, they could be harmful to someone who receives your blood.

Why is this change being made?

Mayo Clinic is committed to lowering the risk of a serious condition called transfusion-related acute lung injury, or TRALI. Additionally, a national agency has included this testing as a new industry standard.

What is TRALI?

TRALI is a rare but serious problem that can result from blood transfusion. If the donated blood contains HLA antibodies, the person who receives the blood reacts to the antibodies. This reaction may cause the lungs to fill with fluid, leading to difficulty breathing and sometimes death.

How will I find out the results of the testing?

It may take several weeks for your test results to be available. If your blood doesn’t contain the HLA antibodies (a negative test result), you will not be contacted and you can continue donating as you had before. If your blood does contain the HLA antibodies (a positive test result), you will receive a letter in the mail. The letter will explain your results and what products you may donate in the future.

If you have any questions or concerns, please contact the Mayo Clinic Blood Donor Program and ask to speak with a nurse.