Borrelia Antibody (Blood)
Does this test have other names?
Borrelia burgdorferi antibodies test, IgM/IgG test, Lyme disease test
What is this test?
This test measures the level of Borrelia antibodies in your blood. Borrelia burgdorferi
bacteria cause Lyme disease.
The bacteria are spread to humans through the bite of an infected tick.
If not treated, Lyme disease can cause meningitis, or an infection of the tissues
covering the brain and spinal cord. It can also cause liver and heart problems; facial
palsy, or the inability to control facial muscles; and other complications that may
show up months or even years later. These include ongoing pain and tiredness, arthritis,
and problems with memory and concentration. Lyme disease is the most common tick-borne
condition in the U.S.
The CDC recommends a two-step evaluation of your blood test. First, your blood sample
is tested through a process called enzyme immunoassay (EIA) or indirect immunofluorescence
assay (IFA). If this is positive for Borrelia antibodies, the sample is put through
an immunoblot test, also known as a Western blot test. This test measures immunoglobulin
G (IgG) and immunoglobulin M (IgM) antibodies in your blood.
You will likely receive a positive diagnosis for Lyme disease if both the EIA/IFA
and the Western blot test are positive. But in some cases, your healthcare provider
may order other tests, such as testing your cerebrospinal fluid.
Why do I need this test?
You might have this test if your healthcare provider suspects that you have Lyme disease.
Symptoms include a red bump that looks like a spider bite that spreads into a red
rash in a classic bull's-eye pattern. You may also have:
Swollen lymph nodes
Muscle and joint aches
What other tests might I have along with this test?
Your healthcare provider may also order a test to look for Borrelia antibodies in
your cerebrospinal fluid if you have signs that your central nervous system has been
affected. This may also be done if the blood test results aren't clear.
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 healthcare
Normal results are negative, meaning that no antibodies were found. But Lyme disease
is hard to diagnose, partly because the antibodies may not show up in your blood for
several weeks. If your results are negative shortly after you've been infected, the
result could be a false-negative.
A positive result means that Borrelia antibodies were found and that you may have
Lyme disease. False-positive results sometimes do occur, so the test could say you
have the infection when you don't.
False-positive results can also happen if you have the autoimmune disease lupus, HIV,
or syphilis. They can also happen if you have Helicobacter pylori bacteria or the
How is this test done?
The test requires a blood sample, which is drawn through a needle from a vein in your
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?
The Lyme disease vaccine might affect your test results. If you are tested too soon
after having been infected, you may get a false-negative result. If you have been
treated with antibiotics, your results may be affected, too.
How do I get ready for this test?
You don't need to prepare for this test. But be sure your healthcare provider 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.