Antinuclear Antibodies (ANA): Symptoms, Diagnosis, Treatment

Overview

Antinuclear Antibodies (ANA) are a group of autoantibodies produced by immune system. Generally, antibodies are proteins made to defend infectious organisms, such as bacteria, viruses and other germs. Sometimes, however, your immune system may mistake normal and naturally-occurring proteins as foreign invaders, and release “autoantibodies” to attack your cells and tissues. Antinuclear antibodies are autoantibodies attacking normal proteins within the nucleus of a cell. Normally, these autoantibodies are in small amounts. Large amount of ANAs may cause autoimmune disease, including systemic lupus erythematosus, rheumatoid arthritis, scleroderma and Sjögren syndrome.

An ANA test can be conducted to examine the existence of antinuclear antibodies. The sensitivity and simplicity of the test makes it essential and popular to evaluate ANA-caused diseases, lupus particularly, since 95% of patients with lupus will test positive for ANA. But a positive ANA test can be seen in 15% of completely healthy people. So, a positive ANA test is not equal to the diagnosis of lupus or other autoimmune diseases.

Causes

ANA is produced by immune system under erroneous judgement of normal proteins as enemies, resulting in attacking proteins in nucleus of cells. It can be detected by an ANA test. A positive ANA test result may be caused by:

  • Abnormal growth of an organ
  • Changes in organ function
  • Destruction of body issues

Noticeably, many healthy people (about 15%) may test positive for ANA if they:

  • Take blood pressure or anti-seizure medication
  • Are women aged 65 or older
  • Have a disease like tuberculosis and mononucleosis

So, more tests and justification from the doctor are needed for a definite diagnosis.

Symptoms of Autoimmune Diseases

Signs or symptoms of an autoimmune disorder may include:

  • Rash
  • Hair loss
  • Light sensitivity
  • Tiredness and weakness
  • Recurring and persistent fever
  • Joint and/or muscle pain
  • Numbness and tingling in your hands or feet

If you have the above symptoms, don’t hesitate to take an ANA test.

Diagnosis (ANA Test)

There are different methods for testing ANAs. The commonly used methods are Fluorescent Antinuclear Antibody (FANA) Test and enzyme-linked immunosorbent assay (ELISA).

FANA test is the traditional and most commonly used method for testing ANA. It will be conducted by taking your blood sample and viewing fluorescent-labeled antibodies on a glass side under the microscope. The pattern and intensity of the fluorescence are essential for the diagnosis.

The results of a FANA test are reported as a titer. For example, a titer result of 1:320 means that one part of blood sample includes 320 parts of saline. This is also the lowest ratio for detecting ANA. The higher the titer is, the greater the amount of autoantibody exist.

ELISA uses antigen-coated microtitre plates for testing ANAs. The well of microtitre plate is coated with a single or many antigens. Blood serum is incubated in the wells of the plate. If antibodies that bind to antigen are present, they will remain after washing, then the enzyme reaction will occur with changes in color.

The results of an ELISA are usually reported as a number with an arbitrary unit of measure (for example, abbreviated as a “U”). A positive result will be a number of units that is above the reference number (cutoff) for the lowest possible value that can be considered as positive.

A positive ANA test means that the autoantibodies exist. Along with the signs and symptoms, chances are that an autoimmune disease do occur. But further tests and evaluation should be accompanied to make a final diagnosis since positive ANA test result may be seen in totally healthy people.

Treatment for Autoimmune Diseases

Different treatment options may be applied depending on the specific disease and symptoms. General types of treatments include:

  • Blood transfusions if blood is affected
  • Physical therapy to help with movement if the bones, joints, or muscles are affected
  • Supplements to replace a substance that the body lacks, such as thyroid hormone and insulin due to the type of autoimmune disease

Immunosuppressive medicines can be taken to reduce the abnormal responses in the immune system. Examples include corticosteroids (such as prednisone) and nonsteroid drugs such as azathioprine, sirolimus, or tacrolimus.

Keyword: Antinuclear Antibodies (ANA).

Related Posts:

ANA Test – Negative, Positive

Autoantibody Testing

Fluorescent Antinuclear Antibody Test

What is ELISA Blood Test?

What Is Lupus? – Basics You Need to Know

What Are Symptoms of Rheumatoid Arthritis?

What Are the Basics of Scleroderma?

* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.