Does this test have other names?
HLA antibody screening, HLA screening assay
What is this test?
This test looks for antibodies against a certain cell marker called a human leukocyte antigen (HLA) in your blood. The test is used if you need an organ transplant, to help find an organ that's as close to yours as possible.
HLAs play an important role in protecting you from infections – but they also make organ transplantation more challenging. HLAs are protein markers found on nearly all of your body's cells. They help tell your immune system which cells belong to your body – and shouldn't be attacked – and which ones are invaders that your immune system needs to fight.
Before an organ transplant, doctors match the recipient and donor HLAs.
An additional issue arises in people who need a transplant and have antibodies against HLAs. Most people don't have these antibodies. However, women who have been pregnant and people who have had previous blood transfusions or transplants may have these antibodies. These antibodies can cause you to reject a transplanted organ immediately, or they may cause the organ to fail over time.
In order to find an acceptable match, it's important that your health care provider measure any HLA antibodies in your bloodstream.
Why do I need this test?
You may have this test if you need an organ from someone else. You may need a transplant if a kidney, lung, or other organ is no longer able to work properly. This test helps give you the best possible chance that the transplant will work well in your body.
What other tests might I have along with this test?
In addition to the HLA test, your doctor may also order:
A test that looks at the type of HLA molecules on the surface of your immune system cells. This helps make sure your donor is a good match.
DNA testing of HLA-related genes. This test requires taking DNA from a sample of cells, usually immune system cells, from a blood sample.
What do my test results mean?
Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider.
Your results will show whether you have certain types of antibodies that could cause a problem after a transplant. Some people have these antibodies, and some don't. Your results will affect the search process for a transplant.
How is this test done?
The test requires a blood sample, which is drawn through a needle from a vein in your arm.
Does this test pose any risks?
Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore.
What might affect my test results?
Past pregnancies, blood transfusions, and transplants can affect your results.
How do I get ready for this test?
Talk with your health care provider about past pregnancies, blood transfusions, and transplanted tissues or organs. In addition, be sure your doctor knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.
- Bass, Pat F. III, MD, MPH
- Fraser, Marianne, MSN, RN