ANA Blood Test

As we all are aware, an antibody is a type of protein generated by the WBCs (white blood cells), so as to defend the body against invading pathogens. Antinuclear antibody is an autoantibody, which is capable of attacking the body's cell nucleus.

It is present in patients who are diagnosed with cancer, infectious diseases, lung diseases, digestive complications, and autoimmune diseases. Also, some treatment drugs trigger the production of such autoantibodies in the body.

In order to check for presence of antinuclear antibodies in the body, a blood test is performed. Abbreviated as ANA test, the Antinuclear Antibody Blood Test is recommended for people who are suspected to have autoimmune disorders and other immune system related medical conditions.

Many of you might be already aware about performing ANA blood test for cancer diagnosis. Detailed information on what is ANA test and interpretation of the test results is explained below.

Antibodies produced by the immune system are released in the bloodstream and circulated to other body parts. Thus, their presence can be detected by examining the blood sample.

The ANA test, also known as Fluorescent Antinuclear Antibody (FANA), is performed for detecting autoimmune diseases, particularly systemic lupus erythematosus and alike medical problems. Similar to other blood tests, the ANA test involves drawing a blood sample from the prospective candidate.

The blood sample is then sent to laboratory to check for presence of antinuclear antibodies.

In the procedure, slides are prepared by adding commercially developed cells. Following this, serum from the collected blood sample is loaded on the prepared slides. In case, the blood contains antinuclear antibodies, they attach to the nucleus of the cells, which are present on the slide.

For ease in identification, another antibody marked with a fluorescent dye is added on the slide. It then binds to the cells, where serum antibodies are already present. The slide is observed under a sophisticated microscope for interpreting the results.

As per medical survey, antinuclear antibodies are found in approximately 5 percent of the general population. The results of an ANA test can be either positive or negative, depending upon the presence or absence of antinuclear antibody in the blood sample.

The slide containing the blood, after being treated with commercially developed cells and antibodies tagged with fluorescent dye, is examined under an ultraviolet microscope. Possible ANA test results are explained below.

Positive ANA Blood Test
ANA test result is positive, if there are fluorescent dyed cells in the slide. The concentration of the autoantibodies in form of titers, along with the type of fluorescent pattern are determined for diagnosing types of autoimmune diseases. High titers mean high amounts of autoantibodies and vice versa.

Coming to fluorescent pattern, a diffuse pattern is related to connective tissue disease and SLE (Systemic Lupus Erythematosus). While a speckled pattern is linked to SLE, scleroderma, rheumatoid arthritis, and polymyositis. Knowing about early symptoms of scleroderma will help you understand it better.

Negative ANA Blood Test
In case of absence of antinuclear antibodies, the blood sample lacks fluorescent cells. Such a case, where there is no fluorescent cell in the slide, is considered negative ANA test result. In order words, if the titer for antinuclear antibody is 1:40 or lesser, it is referred to as negative result.

A positive test result indicates that the patient is having an autoimmune disease or he/she is likely to develop it in the near future. Further examination of the manifested symptoms and medical history are done to diagnose SLE or other autoimmune disorders.

This antinuclear antibodies test alone is reliable to diagnose autoimmune diseases. Nevertheless, if required, the physician may suggest a series of other tests to confirm the suspected health condition.