[Consequences of antinuclear antibodies testing in clinical practice].

Connectivitis or collagenosis are autoimmune multi-systemic diseases. Systemic lupus erythematous (SLE) and Sjogren's syndrome are the most common type after the rheumatoid arthritis. Antinuclear antibodies (ANA), previously called antinuclear factors, are frequently present in connectivitis. Due to their high sensitivity, they may constitute a good screening test. To avoid useless and expensive investigations following a false positive test, a high clinical suspicion is required before any further biological testing. In case of ANA positive testing and low clinical evidence, the presence of anti-DSF70 antibody enables to exclude the diagnostics with a good negative predictive value.