ANA (anti-nuclear antibody) profile
The ANA (anti-nuclear antibody) profile is a laboratory test used to evaluate for the presence of autoantibodies against components of the cell nucleus. This test is primarily used in the diagnosis and management of autoimmune diseases, particularly systemic autoimmune rheumatic diseases (SARDs), including:
- Systemic Lupus Erythematosus (SLE): ANA testing is often used as an initial screening test for SLE. A positive ANA result, along with clinical symptoms such as rash, joint pain, and fatigue, may suggest the presence of lupus. However, a positive ANA test alone is not diagnostic of SLE and requires further evaluation.
- Sjögren's Syndrome: ANA testing may be positive in individuals with Sjögren's syndrome, an autoimmune disorder characterized by dry eyes and mouth due to inflammation of the glands that produce tears and saliva.
- Systemic Sclerosis (Scleroderma): ANA testing is commonly positive in individuals with systemic sclerosis, a connective tissue disease characterized by thickening and hardening of the skin and involvement of internal organs.
- Rheumatoid Arthritis (RA): While RA is primarily diagnosed based on clinical symptoms and other laboratory tests, ANA testing may be positive in some individuals with RA, particularly those with overlapping autoimmune conditions.
- Mixed Connective Tissue Disease (MCTD): MCTD is a rare autoimmune disorder that shares features of SLE, scleroderma, and polymyositis. ANA testing is frequently positive in individuals with MCTD.
- Juvenile Idiopathic Arthritis (JIA): ANA testing may be useful in diagnosing JIA, particularly in certain subtypes such as oligoarticular JIA.
- Other Autoimmune Diseases: ANA testing may also be positive in other autoimmune diseases, including autoimmune hepatitis, inflammatory myopathies, and autoimmune thyroid diseases.