Anti Nuclear Antibody / Factor (ANA / ANF) Test

The Antinuclear Antibody Test is used for the detection of some specific kind of antibodies, called ‘autoantibodies'.

The immune system of your body produces various proteins called antibodies. These antibodies help in detecting any foreign or harmful cells in the body that can cause infections. After detecting these foreign elements, the antibodies go on and destroy these alien cells.

This mechanism of the immune system helps in keeping the body safe against many viruses, bacteria and other disease-causing organisms. However, sometimes the immune system also produces a different kind of antibody, the “autoantibodies.”

These autoantibodies mistakenly identify the body’s own healthy cells as foreign and dangerous cells and go on to destroy them. The proper term for these autoantibodies is antinuclear antibodies (or ANA) because they track the nucleus of healthy cells and destroy them.

The presence of antinuclear antibodies in the body can be related to many autoimmune disorders like Systemic Lupus Erythematosus and Juvenile Idiopathic Arthritis. However, this only happens when the antinuclear antibodies are present in excess in the body.

The Antinuclear Antibody Test is usually recommended for people who show symptoms of an autoimmune disorder or have already been detected with an immune-mediated health issue.

Other Names of the Antinuclear Antibody Test

What Does the Antinuclear Antibody Test Detect/Measure and Who is This Prescribed For?

Here are some conditions to test for which your doctor may prescribe the Antinuclear Antibody Test:

• Systemic Lupus Erythematosus

This autoimmune disorder is an inflammatory disorder of the immune system and can often be a little difficult to diagnose. The Antinuclear Antibody Test is used for the diagnosis of this disorder as the primary diagnostic test. A high level of antibodies along with a speckled pattern can often be related to this disorder.

• Raynaud’s Phenomenon

In this disorder, the fingers, ears, toes and tip of the nose are commonly involved. These areas of the body often feel numb and cool in response to stress or cold temperatures. Doctors suggest the Antinuclear Antibody Test as one of the first diagnostic tests for this disorder.

• Autoimmune Hepatitis

This autoimmune disease is caused of a condition wherein the antinuclear antibodies attack the person’s liver. The Antinuclear Antibody Test is used in the diagnosis of Autoimmune Hepatitis when the liver starts showing signs of dysfunction.

Apart from these medical conditions, people with any of the following symptoms are also advised to take the ANA Test:

• Tiredness
• Persistent or recurring fever
• The appearance of a butterfly-shaped red rash on the cheeks and bridge of the nose
• Muscle and joint pain
• Swelling and stiffness
• Sensitivity to light
• No sensation or numbness or tingling in the hands or feet

This table is meant to guide you in understanding what the different test results mean and how they should be interpreted:

• ANA Negative Test Result

With no presence of antinuclear antibodies detected in your blood, you are less likely to develop or have an autoimmune disorder. However, if you have any other symptoms, your doctor may suggest some other tests that detect the presence of other antibodies.

Having an Antinuclear Antibody negative test result does not guarantee that you don’t have autoimmune diseases.

• ANA Positive Test Result

The laboratory test results will also inform you of the titer (or level) of the antinuclear antibodies found in your blood sample. The titer may be as follows:

• 1:40
• 1:80
• 1:160
• 1:320
• 1:640

1:40 is the least level of ANA and it increases as you progress in the ratios. So, you can relate 1:640 with the highest amount of ANA present. The staining pattern (as explained in the test parameters) will also be mentioned in the lab ANA test report.

Having an Antinuclear Antibody positive test result is not a confirmation of an autoimmune disease. Many people with antinuclear antibodies present in their bodies still do not have any autoimmune diseases.

However, if you have any symptoms in addition to having a positive ANA test result, your doctor will prescribe additional diagnostic tests.

You can also get a false-positive test result, especially if you are a female above 65 years of age, have an infection like tuberculosis or regularly take blood pressure or anti-seizure drugs.

The Antinuclear Antibody blood sample is tested for the presence or absence and if present, the level of antinuclear antibodies circulating in the body.

Test Preparation

A blood draw is a way to collect the Antinuclear Antibody blood sample, which is then tested for the level and the pattern (if any) of the antinuclear antibodies in the blood.

No fasting is required or any other preparation before the blood sample is taken. However, if you are taking any regular medication or supplements, you should discuss them with your healthcare professional. The doctor might ask you to temporarily stop taking the medication if they feel that it can interfere with or affect the test results in any way.

There are no major risks involved typically in giving your blood sample, but some people often feel a little dizzy or weak immediately after.

You may carry a small snack with you if you feel weak after the blood sample is taken. You should also ask someone to drive you back home if you don’t feel comfortable enough to drive yourself.

Test Inclusions: What Parameters Are Included?

The Antinuclear Antibody Test procedure is performed to get information on two specific parameters: the level, which is also called the ‘titer’ of antinuclear antibodies present in the blood and the pattern in which the antinuclear antibodies have been found in the blood sample.

• Antinuclear Antibody ‘Titer’ or Level

The titer or level of the ANA test provides an estimation of the number of antinuclear antibodies present in the blood.

To check this level of ANAs, a blood sample is taken. This serum from blood is separated, which is then mixed with a liquid to perform the test for ANA.

If ANA antibodies are present this sample is tested again and again in different ratios of the blood sample and a chemical liquid. Every time one ratio shows the presence of antinuclear antibodies, a new and stronger solution is prepared (in a different ratio than the previous one) and the test for the presence of antinuclear antibodies is conducted again.

If antinuclear antibodies are present even at the strongest ratio or the strongest solution made after mixing the blood sample and the chemical liquid, this indicates that there is a very high number of antibodies in the person’s blood sample.

• Antinuclear Antibody Pattern

There are several possible patterns in which antinuclear antibodies can be found in the blood sample. These patterns are also called the ANA staining patterns, which are the patterns in which the antinuclear antibodies stain the blood sample when a chemical is added to the blood sample for testing.

It is established that these staining patterns are loosely related to the underlying autoimmune disease (if any) that these ANAs can cause in a person.

The possible patterns are:

• Homogenous pattern
• Speckled pattern
• Nucleolar
• Centromere

Out of the following, the homogenous staining pattern is considered to be the most common and also the least concerning pattern (or least harmful) of antinuclear antibodies.

Systemic Lupus Erythematosus, Juvenile Idiopathic Arthritis, Sjögren’s Syndrome, Polymyositis, Dermatomyositis