Description
Overview: Your immune system normally produces antibodies to fight off infections. However, in autoimmune disorders, it mistakenly produces “autoantibodies” that attack your own tissues. Anti-nuclear antibodies (ANAs) are a group of autoantibodies that specifically target the nucleus (the command center) of your cells. The ELISA (Enzyme-Linked Immunosorbent Assay) method is a highly sensitive technique used to detect the presence of these antibodies in your blood.
Clinical Significance: A positive ANA test is a primary indicator of a systemic autoimmune rheumatic disease (SARD). While a positive result is not a definitive diagnosis on its own, it is a crucial first step in investigating conditions such as:
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Systemic Lupus Erythematosus (SLE): About 95% of people with lupus test positive for ANA.
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Sjögren’s Syndrome: An autoimmune disorder that affects the glands that produce tears and saliva.
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Scleroderma: A chronic connective tissue disease.
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Mixed Connective Tissue Disease (MCTD).
When is this test recommended?
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To screen for an underlying autoimmune disorder when a patient presents with symptoms like chronic fatigue, persistent joint pain or swelling, unexplained fevers, or a butterfly-shaped rash across the cheeks and nose.
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To monitor the progression or disease activity in patients already diagnosed with certain autoimmune conditions.
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Note: A positive ANA result is usually followed by more specific antibody tests (like anti-dsDNA, anti-Sm) to help pinpoint the exact diagnosis.
Sample Requirements:
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Specimen: Serum.
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Container: Gold Top (SST) or Red Top Tube.
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Preparation: No fasting is typically required.
