ANA tests are one of the tools that clinicians use to help diagnose lupus.
ANA stands for antinuclear antibodies. In this article, we will explore antinuclear antibodies and see how they are different in the body of a person with an autoimmune disease, like lupus.
The testing and diagnosis process for lupus can be long and confusing. In addition to tracking symptoms, it is helpful to understand the laboratory tests used by clinicians to monitor the body on a biological level.
What are Antinuclear Antibodies (ANA)?
Before jumping to antinuclear antibodies, we will start with antibodies. Antibodies are proteins made by your immune system that help your body recognize and fight harmful substances, such as bacteria and viruses, by activating the immune system to target them. You can think of antibodies as the soldiers that protect your body from bad, foreign invaders.
Sometimes, antibodies mistakenly attack healthy cells and tissues in the body. This is known as an autoimmune response. Antibodies that target healthy proteins specifically in the nucleus (brain) of your cells are called antinuclear antibodies (ANA). To continue the analogy from above, ANAs are rogue soldiers that misidentify the cells they are supposed to ignore, and attack them in error.
NOTE: Most people have some ANA, but having too many of these proteins puts you at an increased risk for developing an autoimmune disease, such as lupus.
Who Gets ANA Tests?
Typically, an ANA test is ordered when someone has symptoms that may indicate a systemic autoimmune disease. Some examples of symptoms that may prompt a doctor to order the test include (but are not limited to):
- low-grade fevers
- arthritis-like pain
- muscle pain
It’s important to know that an ANA test is used hand-in-hand with many other factors to diagnose an autoimmune disease. Your doctor will also consider your symptoms, physical examinations, medical history, and other test results.
Quick Stats on ANA Tests and Lupus
97% of people with lupus will have a positive ANA test.
Between 5-20% of the normal population will have a positive ANA test. A positive test can be a false-positive, or indicate other conditions, such as thyroid disease, certain liver conditions, or other autoimmune diseases.
97% of people with lupus will have a positive ANA test
What Should I Know About ANA Tests and Lupus?
- There is no one definitive test for lupus – an ANA test is just one tool used to help diagnose lupus.
- The ANA test is not a specific test for lupus. This means that most people with lupus will have a positive ANA test, but not everyone with a positive ANA test has lupus.
- Some medications can produce a positive ANA test, so be sure to tell your doctor about any prescription or over-the-counter drugs you take.
- Test results can fluctuate over time and when they are performed at different labs. However, if you have active lupus, your ANA test will probably be positive at most labs, most of the time.
How is an ANA Test Performed?
- An ANA test is performed in a laboratory, using a sample of your blood.
- The test shows if your immune system is producing antinuclear antibodies. A positive ANA test means antinuclear antibodies are present.
- The most common tests used for detecting and measuring ANAs are indirect immunofluorescence and enzyme-linked immunosorbent assay (ELISA).
What Should I Do if My ANA Test is Positive?
- Your doctor will interpret your ANA test in the context of your symptoms, other lab work, and your medical history, including family history. Keeping a symptom journal or using digital tools, such as Karate Health, can help you be better prepared to go over your symptoms with your doctor.
- Remember, a single positive ANA does not imply autoimmune disease. And a positive ANA test does not require immediate treatment. Your doctor will take the ANA test results in context with many other factors.