Tags: ana | antibody | blood | test | positive ana

What Does a Positive Antinuclear Antibody Test Mean?

Wednesday, 30 April 2014 12:43 AM

Antibodies are made by the white blood cells in our body to recognize and fight infectious organisms that may affect the body. Sometimes, these antibodies make a mistake by identifying the normal proteins in our body as foreign. They are known as antinuclear antibodies or ANA.
The body responds to external pathogens (antigens) in the blood, like virus, bacteria etc., by fighting back with the help of antibodies. The antibody–antigen reaction induces immunity in the body. Antinuclear antibodies are special kinds of antibodies detected in the blood, which are found in autoimmune diseases. Autoimmune diseases present with inflammation of the body tissues.
These antinuclear antibodies are able to attach to some structures in the nucleus of the cell like DNA.  The ANA test is a blood test used to check the levels of anti-nuclear antibodies. A blood sample is taken in the fasting state to test for antinuclear antibody. We can detect the antinuclear antibodies in the blood by fluorescent test technique. The blood is exposed to the cells in the laboratory and the reaction to the nucleus of cells is determined.
It is interesting to note that a positive ANA does not always indicate the presence of autoimmune disease in the body. Sometimes, some medications can lead to a positive ANA test. People older than 60 can also have abnormally positive ANA. In normal population, about 5 percent of the people can show a positive ANA and so by itself, a positive antinuclear antibodies does not indicate the presence of an autoimmune disease.
Many autoimmune disorders like autoimmune thyroiditis, SLE, scleroderma etc., are diagnosed with the help of a positive ANA test. Positive ANA blood test can indicate a lot of other autoimmune disorders like ulcerative colitis, autoimmune hepatitis, scleroderma, multiple sclerosis, cystic fibrosis, rheumatoid arthritis, vitiligo, childhood diabetes mellitus etc.
In people with positive ANA, the antinuclear antibodies are present in low titers in the blood. Severe viral and bacterial infections and cancer may also cause a positive antinuclear antibody test.
It is always recommended to confirm the diagnosis of any autoimmune problem by other blood tests and symptoms. Many other tests can assist in making correct diagnosis of autoimmune problems.
After a positive ANA test, one can look for subtypes of antinuclear antibodies like anti-Ro antibodies, anti-Sci70 antibodies, anti-sp100 antibodies, and so on. If a serum dilution of 1:160 detects the antinuclear antibodies, then a positive ANA is interpreted. Dilutions like 1:120 can show positive ANA in 20 percent of elderly individuals. 

© Newsmax. All rights reserved.

1Like our page
Autoimmune diseases are becoming common of late. Antinuclear antibody test, commonly known as ANA test, is used to screen for these problems. This is a blood test that helps in detecting these special antibodies.
ana, antibody, blood, test, positive ana
Wednesday, 30 April 2014 12:43 AM
Newsmax Media, Inc.

The information presented on this website is not intended as specific medical advice and is not a substitute for professional medical treatment or diagnosis. Read Newsmax Terms and Conditions of Service.

Newsmax, Moneynews, Newsmax Health, and Independent. American. are registered trademarks of Newsmax Media, Inc. Newsmax TV, and Newsmax World are trademarks of Newsmax Media, Inc.

© Newsmax Media, Inc.
All Rights Reserved