What is an ANA Test?
An ANA test, also known as the antinuclear antibody test, is designed to detect antinuclear antibodies in a sample of blood. The acronym ANA refers to antinuclear antibodies that are automatic in the sense that they automatically bind to certain surfaces within the nucleus of cells. While a healthy person should possess a certain amount of antibodies to guard against invading bacteria, antinuclear antibodies work against this self-defense mechanism. In fact, a high level of antinuclear antibodies present may indicate that the immune system is capable of mistakenly launching an attack on healthy tissue. This condition is known as autoimmunity. The ANA test was developed by Dr. George Friou in 1957 to help diagnose autoimmune disorders. Most commonly, an ANA test is performed when lupus is suspected. However, the clinician may order an ANA test to rule out various other autoimmune disorders when certain symptoms are present, such as frequent joint pain, skin rashes, chronic fatigue, or a
ANA stands for anti-nuclear antibody. This test detects a group of antibodies directed against components of nucleus of the cell, such as DNA and ribonucleoproteins (RNP). The individual antibodies include anti-DNA antibodies and the various anti-ENA antibodies (see below). The ANA test is used as a screening test for these autoantibodies which may then be identified individually by other tests. The ANA test is positive in 95% of people with lupus but only about 5% of healthy people. It can also be positive in people with related autoimmune conditions (sometimes called connective tissue diseases) such as dermatomyositis, polymyositis, and systemic sclerosis (scleroderma). It is sometimes positive in people with other types of disease such as chronic infection or certain malignancies (cancers). It is therefore not diagnostic of lupus, but it is important supporting evidence when other features (symptoms, signs and other laboratory tests) suggest lupus. Why is the ANA test done to diagno
ANA stands for anti-nuclear antibody. This test detects a group of antibodies directed against components of nucleus of the cell, such as DNA and ribonucleoproteins (RNP). The individual antibodies include anti-DNA antibodies and the various anti-ENA antibodies (see below). The ANA test is used as a screening test for these autoantibodies which may then be identified individually by other tests. The ANA test is positive in 95% of people with lupus but only about 5% of healthy people. It can also be positive in people with related autoimmune conditions (sometimes called connective tissue diseases) such as dermatomyositis, polymyositis, and systemic sclerosis (scleroderma). It is sometimes positive in people with other types of disease such as chronic infection or certain malignancies (cancers). It is therefore not diagnostic of lupus, but it is important supporting evidence when other features (symptoms, signs and other laboratory tests) suggest lupus.
