Hello~An antinuclear antibody test looks for autoimmune diseases such as lupus or rheumatoid arthritis. The ANA blood test is just one part of a doctor's autoimmune disease diagnosis, along with a listing of your symptoms, a physical exam, and other tests.
The ANA test detects these autoantibodies in the blood. ANA react with components of the body's own healthy cells and cause signs and symptoms such as tissue and organ inflammation, joint and muscle pain, and fatigue. ANA specifically target substances found in the nucleus of a cell, hence the name "antinuclear."