An ANA blood test (antinuclear antibody test) is usually performed on a blood sample as part of the diagnostic process for certain autoimmune diseases.1 It is usually ordered along with other blood tests, such as CBC and ESR—and all of the results are considered together.
An ANA should not be used as a screening test but should only be checked in people in which there is a high pre-test probability of rheumatic diseases, such as lupus or Sjögren's syndrome. It should not be checked as part of the work-up for weight gain/loss, chronic fatigue, brain fog, or other vague symptoms.
