ANA (Antinuclear Antibody) Test
Reviewed
Also called: Antinuclear antibody panel, Fluorescent antinuclear antibody (FANA), ANA reflexive panel
An ANA test is a blood test that looks for antinuclear antibodies in your blood.
Specimen: Blood
Why this test may be ordered
- Fever
- Rash, blisters, or skin color changes
- Fatigue
- Joint pain, stiffness, and swelling
- Muscle pain
Preparation and collection
Some medicines may affect the results of your ANA test. You may need to stop taking certain medicines before this test, so tell your provider about everything you take. But don't stop taking any medicines unless your provider tells you to.
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
There is very little risk to having 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.
Understanding results
Results from an ANA test alone cannot diagnose a specific disease. Your provider will use your ANA test results along with other blood and imaging tests and information about your health to make a diagnosis.
- Negative: A negative result on an ANA test means that antinuclear antibodies were not found in your blood, and you're less likely to have an autoimmune disorder. Limitation: But a negative ANA test doesn't completely rule out the possibility that you could have an autoimmune disorder. Next step: If you have questions about your results, talk with your provider.
- Positive: A positive result on an ANA test means that antinuclear antibodies were found in your blood. Limitation: Having antinuclear antibodies in your blood doesn't always mean you have a disease. Some healthy people have antinuclear antibodies in their blood, and levels tend to increase with age. Also, certain medicines can cause antinuclear antibodies. Next step: If your ANA test results are positive, your provider will likely order more tests to make a diagnosis.
- You may feel a little sting when the needle goes in or out; slight pain or bruising at the puncture site is possible but most symptoms go away quickly.
- A negative result does not completely rule out an autoimmune disorder.
- A positive result does not always mean you have a disease; some healthy people, especially women over 65, may have a positive result, and certain medicines can also cause antinuclear antibodies.
What to do next
If your ANA test results are positive, your provider will likely order more tests to make a diagnosis. If you have questions about your results, talk with your provider.
- What do my ANA test results mean in my specific situation?
- Do I need any follow-up tests based on my results?
- Should I stop any of my current medicines before this test?
Evidence source
Source: U.S. National Library of Medicine (MedlinePlus). Practices and reference ranges may differ in your country.
U.S. National Library of Medicine: ANA (Antinuclear Antibody) Test