ANA Titer

Antinuclear Antibodies (ANA) Titer quantifies the concentration of ANA in the blood if the ANA screen is positive. The blood serum is serially diluted (e.g., 1:40, 1:80, 1:160), and the highest dilution showing fluorescence is reported. Higher titers (e.g., ≥1:160) are more likely to be clinically significant for autoimmune disease, though interpretation depends on the pattern and clinical context.