An anti-double stranded DNA (anti-dsDNA) test is a blood test that looks for antibodies against double stranded DNA in your bloodstream. These antibodies are a type of autoantibody, which means they mistakenly target and react with a person's own tissues or organs. The presence of anti-dsDNA antibodies is particularly associated with systemic lupus erythematosus (SLE), a chronic autoimmune disease where the immune system attacks the body's own cells, causing widespread inflammation and tissue damage in the affected organs.
The anti-dsDNA test is highly specific for diagnosing and monitoring the activity of SLE. Not all people with SLE will have anti-dsDNA antibodies, but their presence is strongly suggestive of the condition, especially when accompanied by typical clinical symptoms and other diagnostic criteria. The level of anti-dsDNA antibodies can also fluctuate with disease activity; higher levels are often seen in more active phases of the disease and can be used to monitor disease progression or response to treatment.
Besides its role in diagnosing SLE, the test can help differentiate SLE from other autoimmune conditions, as anti-dsDNA antibodies are rarely found in diseases other than SLE. This makes the anti-dsDNA test a valuable tool in the diagnostic process and in managing the care of patients with suspected or confirmed SLE.