Borrelia burgdorferi antibodies test, IgM/IgG test, Lyme disease 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.
Lyme disease is the most common tick-borne illness in the U.S. If not treated, Lyme disease can cause an infection of the tissues covering the brain and spinal cord (meningitis). It can also cause:
Liver and heart problems
Inability to control facial muscles (facial palsy)
Problems that may show up months or years later, such as ongoing pain and tiredness, arthritis, and problems with memory and concentration
The CDC advises a 2-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. This is 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 diagnosis for Lyme disease if both the EIA/IFA and the Western blot test are positive. But in some cases, you may also have other tests, such on your cerebrospinal fluid (CSF).
You may need this test if your healthcare provider thinks that you have Lyme disease based on recent travel, physical exam, and symptoms. 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
You may also have a test to look for Borrelia antibodies in your cerebrospinal fluid (CSF) 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. CSF is the liquid that surrounds the brain and spinal cord.
Test results may vary depending on your age, gender, health history, the method used for the test, and other things. Your test results may not mean you have a problem. Ask your healthcare provider what your test results mean for you.
A negative result means that no antibodies were found. But Lyme disease is hard to diagnose. This is 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. This means 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 Epstein-Barr virus.
The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand.
Having a blood test with a needle carries some risks. These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore.
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.
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 illegal drugs you may use.