Antinuclear Antibodies (ANA)
An antinuclear antibody (ANA) test measures the amount and pattern of Reference antibodies Opens New Window in your blood that work against your own body (autoimmune reaction). If there are more antibodies in the blood than normal, the test is positive. When the test is positive, most labs do other tests right away to look for the cause. These tests can find out which antibodies are in the blood in higher amounts than normal.
A positive ANA test may be caused by:
- Autoimmune connective tissue diseases.
- Reference Rheumatoid arthritis Opens New Window. More than one-third of people with rheumatoid arthritis have a positive ANA test.
- Reference Systemic lupus erythematosus (SLE) Opens New Window. Almost all people with SLE have a positive ANA test. But most people with a positive ANA test do not have SLE.
- Reference Scleroderma Opens New Window.
- Reference Sjögren's syndrome Opens New Window.
- Reference Juvenile idiopathic arthritis Opens New Window.
- Reference Polymyositis Opens New Window.
- Reference Raynaud's syndrome Opens New Window.
- Autoimmune diseases of other organs. Examples
- Reference Addison's disease Opens New Window.
- Diseases of the blood cells, such as Reference vitamin B12 deficiency Opens New Window, Reference idiopathic thrombocytopenia (ITP) Opens New Window, and Reference hemolytic anemia Opens New Window.
- Liver disease, such as Reference hepatitis Opens New Window.
- Thyroid disease, such as Reference Hashimoto's thyroiditis Opens New Window.
- Medicines, such as those used to treat high blood pressure, heart disease, and tuberculosis (TB).
- Viral infections.
|By:||Reference Healthwise Staff||Last Revised: Reference June 4, 2012|
|Medical Review:||Reference Anne C. Poinier, MD - Internal Medicine
Reference Kathleen Romito, MD - Family Medicine