An antinuclear antibody (ANA) test is conducted to detect autoimmune diseases such as rheumatoid arthritis or lupus. While a doctor is diagnosing an autoimmune disease through physical exam, symptoms, and various test, ANA blood test is just one of the necessary tests to be conducted.
What are antibodies?
Antibodies are proteins used by the immune system to fight off viruses, bacteria, and other germs. In the process of fighting invaders, your immune system can mistake your own body as part of foreign invaders. Special antibodies called autoantibodies are released, which attack your tissues and cells. Autoantibodies may damage your muscles, skin, joints, and other parts of your body.
Antinuclear antibodies (ANAs) are therefore a form of autoantibody that attacks proteins in your cells. Autoimmune disease people will test positive for ANAs.
Why a doctor order for antinuclear antibody test
An antinuclear antibody test may be ordered if you have symptoms of autoimmune disease such as mild fever, rash, tiredness, joint or muscle pain, hair loss, light sensitivity, weakness, and numbness and tingling in your feet or hands.
Getting ready for the test
There’s no serious preparation for the ANA test. You may stop eating a few hours before the test commenced. Moreso, ANA test results may be affected by some medications, so let your doctor know the vitamins, supplements, and medicines you take.
Process of the test
A sample of your blood will be taken by a lab tech through the vein in your arm. He begins by tying a band around the upper part of your arm to pump blood into your vein and swell up. Next, he uses an antiseptic to clean the area and then insert a needle into your vein to collect your blood into a tube or vial.
In a couple of minutes, the blood sample is drawn. Then the needle and the band are removed. Followed by the application of a piece of gauze and a bandage over the area to stop the bleeding. The blood sample is then moved to the lab for the test. The lab tech checks to see if there are antinuclear antibodies in your blood.
Is there any risk?
A few risks are attached to the blood test, starting with the feeling of a slight sting as your blood is drawn. You may also have a small bruise. At the same time, there’s a slight chance of bleeding, soreness, or dizziness.
What does my result mean?
The result of your test is positive if antinuclear antibodies are found in your blood. It is negative if none is found. A positive result can simply mean you have an autoimmune disease such as lupus – a disease that damages skin, joints, and other organs. Around 95 percent of people that have lupus will test positive for antinuclear antibodies.
A positive result of your test may also mean you have one of the other autoimmune diseases below:
1. Polymyositis: a disease that causes weakness of the muscle.
2. Scleroderma: a disease of the connective tissue.
3. Mixed Connective Tissue Disease: a condition with the symptoms of polymyositis, lupus, and scleroderma.
4. Juvenile Chronic Arthritis: autoimmune arthritis which affects children.
5. Rheumatoid Arthritis: causes damage to the joints, swelling, and pain.
6. PolyarteritisNodosa: an uncommon disease that causes blood vessels to swell up and damage the organ.
7. Dermatomyositis: an uncommon disease that causes rashes and weak muscles.
Even if the result of your antinuclear antibody (ANA) is negative, you likely have an autoimmune disease. In case your symptoms don’t go away, then you might need other tests.
The result of the antinuclear antibody (ANA) can also be positive if one of these conditions is positive in your body system:
- Thyroid disease such as Grave’s disease and Hashimoto’s thyroiditis.
- Raynaud’s syndrome is a disease that makes your toes and fingers turn blue and makes you feel cold.
- Inflammatory bowel disease
- Liver disease includes primary biliary cirrhosis and autoimmune hepatitis.
- Lung disease like idiopathic pulmonary fibrosis
Approximately 20 percent of healthy people will test positive for an antinuclear antibody, even if they don’t have an autoimmune disease.
You’re likely to have a false-positive result if
- You’re a woman age 65 and older
- You have infections like tuberculosis or mononucleosis
- You take anti-seizure or blood pressure drugs
ANA test only shows you have an autoimmune disease but doesn’t confirm the exact type. If you test positive for ANA, you might need an additional ANA test that is specific to certain diseases such as:
- ENA panel – shows your doctor the type of autoimmune disease that you have.
- Anti-Double-Stranded DNA (anti-dsDNA) – diagnoses lupus.
- Anti-Centromere – diagnoses scleroderma.
- Anti-Histone – diagnoses lupus that is caused by the medicine you take.
Have a clear understanding of your antinuclear antibody (ANA) test and go for other tests that are necessary to confirm your diagnosis. Moreso, ask if your test will affect your treatment in any way.