Anti Nuclear Antibody (ANA-Elisa) Test is a blood test used to detect the presence of antinuclear antibodies in the blood. These are antibodies produced by the immune system of the body against protein markers found in the nucleus of its own cells. A doctor may recommend an ANA (Elisa) Test when you have symptoms of autoimmune diseases like severe fever, difficulty in breathing, vision difficulty, hair loss, weakness, abnormal growth, severe abdominal pain, etc.