Lyme Disease Tests
Reviewed
Also called: Lyme antibodies detection, Borrelia burgdorferi antibodies test, Borrelia DNA Detection, IgM/IgG by Western Blot, Lyme disease test (CSF), Borrelia antibodies, IgM/IgG
Lyme disease tests look for signs of infection in a sample of your blood or cerebrospinal fluid (CSF).
Specimen: Blood or cerebrospinal fluid (CSF)
Why this test may be ordered
- To help diagnose Lyme disease infection if you have symptoms and possible tick exposure.
- To evaluate whether Lyme disease has spread to your nervous system (CSF test).
Preparation and collection
You don't need any special preparations for a Lyme disease blood test. For a lumbar puncture, you may be asked to empty your bladder (pee) and bowels (poop) before the test.
Lyme disease testing is usually done on a sample of blood. In certain cases, a CSF test may be done. To get a sample of your CSF, a provider will do a procedure called a lumbar puncture, also known as a spinal tap.
There is very little risk to having a blood test or a lumbar puncture. With a blood test, you may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly. You may also have some bleeding at the site or get a headache.
Understanding results
Lyme disease is difficult to diagnose. The symptoms are common to many conditions, and test results alone can't diagnose the disease.
- Negative: A negative blood test result means that antibodies to fight the Lyme disease bacteria were not found in your blood. If you had symptoms for longer than 30 days before your test, you probably don't have Lyme disease. Limitation: If your test was done too soon, you could be infected even though your test was negative. Next step: But if you had symptoms for less than 30 days before you gave your blood sample, you may need to have another Lyme disease test.
- Positive: A positive blood test result means that antibodies to fight the Lyme disease bacteria were found in your blood. If the second test is positive and you have symptoms of infection, you probably have Lyme disease. Limitation: But positive test results don't always mean that Lyme disease is causing your symptoms. You could have antibodies from a past case of Lyme disease that your body successfully fought off months or even years ago. Next step: In this case, the Centers for Disease Control and Prevention (CDC) recommends a second blood test on the same blood sample.
- Test results alone cannot diagnose Lyme disease; your healthcare provider must consider your medical history, exposure, symptoms, and possibly other tests.
- Blood tests may be negative early in infection (false negative) because it takes weeks for antibodies to appear.
- Positive blood tests may be false positive (e.g., from other bacterial infections or autoimmune diseases) or from a past resolved infection.
- CSF test negative does not rule out nervous system involvement; more tests may be needed.
What to do next
To make a diagnosis, your provider will consider your test results along with your medical history, exposure, and symptoms. You may also need other tests.
- What were my potential tick exposures?
- When did my symptoms start?
- Do I have any other conditions that could affect test results?
Evidence source
Source: U.S. National Library of Medicine (MedlinePlus). Practices and reference ranges may differ in your country.