Anti ds-DNA Antibody, EIA

Anti-dsDNA is a type of autoantibody known as antinuclear antibodies (ANA). Under normal circumstances, these antibodies help protect us from infections, but autoantibodies are produced when the immune system confuses the body’s own cells with foreign invaders. This leads to the immune system mistakenly attacking healthy cells, causing autoimmune disorders. While low levels of anti-dsDNA can be found in several conditions, it is mainly linked to systemic lupus erythematosus (SLE), a long-term inflammatory autoimmune disease affecting kidneys, joints, blood vessels, skin, heart, lungs, and brain. The Anti ds-DNA Antibody, EIA test can help diagnose lupus and differentiate it from other autoimmune disorders such as mixed connective tissue disease and lupus nephritis.

The doctor may suggest the Anti ds-DNA Antibody, EIA test if the individual has a positive antinuclear antibody (ANA) test along with symptoms suggestive of lupus, such as persistent fatigue, joint pain, and a characteristic butterfly-shaped rash across the nose and cheeks. It is also periodically used to assess disease activity in people who have already been diagnosed with lupus and if there are risk factors such as aging, obesity, and a family history of autoimmune diseases.

Generally, an overnight fast (8-12 hours) is preferred but not mandatory for this test. However, it's advised to inform the doctor about any other medications or supplements being taken, as certain medications may affect the test results. Additionally, telling a detailed medical history and discussing symptoms can help the doctor correlate the clinical and laboratory findings. 

Lab test results may vary across laboratories based on the methodologies used and reference ranges. The Anti ds-DNA Antibody, EIA test conducted through the enzyme-linked immunosorbent assay (EIA) method is one of the most sensitive screening tests for detecting even subtle levels of ds-DNA. This method uses enzymes to find the antibodies in the blood. It is a faster and more automated method. 

Do not try to self-medicate at home based solely on these results. Always consult a doctor for a proper understanding of the test results. The insights from this test help the doctor tailor appropriate treatment plans.