This test is also known as ANA, Fluorescent Antinuclear Antibody, FANA and Antinuclear Antibody Panel. Primarily, this test is used to diagnose autoimmune disorders in a person, especially the systemic variety. It is widely used in the diagnosis of systemic lupus erythematosus (SLE). Anti Nuclear Antibodies (ANA) are actually a group of autoantibodies produced by our immune system. Issues occur when these start attacking the cells, causing them harm. This test may be used in conjunction with autoantibody tests for an accurate diagnosis.