An antinuclear antibody (ANA) test measures the amount and pattern of antibodies in your blood that work against your own body (autoimmune). The results of an ANA test are usually given in titers. A titer is a measure of how much the blood sample can be diluted before the presence of the antibodies can no longer be detected. [ Basically the titer its a ratio referring to a concentration of antibodies ] For example, a titer of 1 to 40 (1:40) means that antibodies can be detected when 1 part of the blood sample is diluted by up to 40 parts of a salt solution (saline). A larger second number means there are more antibodies in the blood. Therefore, a titer of 1 to 80 indicates more antibodies in the blood than a titer of 1 to 40. There are different subtypes of ANA which may have a range of normal values. Normal values may vary from lab to lab. Results will usually be available in about 1 week. Antinuclear antibodies, may have Normal titer of 1:40 or less.
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