What Are Antinuclear Antibodies?

Antinuclear antibodies (ANA), also known as anti-nucleic acid antigen antibodies, are a group of autoantibodies against DNA, RNA, proteins or molecular complexes of these substances in the nucleus of cells. Each ANA can be distinguished according to the different properties of its molecules in the nucleus, such as: anti-DNA antibodies; anti-histone antibodies; anti-non-histone antibodies; Each category is subdivided into many categories due to different antigenic characteristics. Therefore, in the broad sense, ANA is a group of autoantibodies with different clinical significance. The more accurate name should be the antinuclear antibody spectrum. ANA is mainly found in IgG and is also found in IgM, IgA, and even IgD and IgE. Antinuclear antibodies can recognize various nuclear components and can be characteristically found in many autoimmune diseases, especially rheumatoid diseases. They can judge disease activity and prognosis, observe treatment response, and guide clinical treatment.

Basic Information

Chinese name

Antinuclear antibody

Foreign name

antinuclear antibody

Alias

Antinucleic acid antigen antibody

Distribution

In serum, pleural fluid, joint synovial fluid, and urine

Clinical significance of antinuclear antibodies

Antinuclear antibody tests are screening tests for autoimmune diseases. Antinuclear antibodies show positive rates of varying degrees in various autoimmune diseases, such as systemic lupus erythematosus (SLE, 95% to 100%), rheumatoid arthritis (RA, 10% to 20%), mixed Connective tissue disease (MCTD, 80% to 100%), Sjogren's syndrome (SjS, 10% to 40%), systemic scleroderma (85% to 90%), lupus hepatitis (95% to 100%), Primary biliary cirrhosis (95% to 100%), etc., but after corticosteroid treatment, the positive rate can be reduced. Antinuclear antibodies are positive in about 20% to 50% of IgG type ANA in rheumatoid patients. The positive rate of pediatric rheumatoid ANA is about 19% to 35%, and those with iridocyclitis are high (50% 90%), so ANA positive indicates that rheumatoid arthritis may cause chronic ciliary body inflammation. It has been found that 75% of rheumatoid patients have polymorphonuclear leukocyte-specific ANA or anti-neutrophil cytoplasmic antibody (ANCA) that can destroy the leukocyte nuclei.

An autoimmune disease can detect a variety of autoantibodies, and the detection of an antinuclear antibody can also involve a variety of related autoimmune diseases, so clinicians often need to refer to multiple immune indicators, combining clinical manifestations and other auxiliary examination Analyze to make a diagnosis.

Anti-nuclear antibody normal value reference range

Negative or <32