ANA Test - Purpose & Results

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Is a result of 0.47 a positive result or negative result
There are two test methods of ANA - IFA and Immunoassay. IFA is reported in a ratio, like 1: 240, immunoassay is reported as a number with an arbitrary unit of measure. Your number looks like the one from Immunoassay. It depends on the cutoff provided by your lab, the cutoff can vary among various labs. The lab I'm familiarr with takes <=1.0 U as negative.
Is there one or two results that can pinpoint if its autoimmune or another problem?
No. There're many types of antibodies, each antibody can relate to a couple of autoimmune disease, so the dr. has to evaluate which disease is likely, then order relevant antibody tests.
I recently had my ANA and RA Factor lab test drswn. Both came back positive. Is that anythingvto be concerned about??
Hello, ANA and RA Factor are tests for autoimmune disease, if you also have symptoms, it's likely you have RA.

ANA test is to detect and help diagnose certain autoimmune disorders, such as lupus and Sjögren syndrome, among other types.

A positive ANA test result means that autoantibodies are present. In a person with signs and symptoms, this suggests the presence of an autoimmune disease, but further evaluation is required to assist in making a final diagnosis. Again, some people without disease can have a positive ANA test.

Positive ANA test results may be reported in different ways, depending on the test method.

Amount of autoantibody present

Indirect fluorescent antibody (IFA)—the results are reported as a titer. Titers are expressed as ratios, which are obtained by diluting a portion of the blood sample with saline (salt water). For example, a titer result 1:320 means that one part blood sample was mixed with 320 parts of saline and this was lowest ratio at which ANA was still detected. The lower the dilution ratio at which ANA is still detected, the higher the titer and the greater the amount of autoantibody present.

Immunoassay (enzyme linked immunosorbent assay, ELISA, or enzyme immunoassay, EIA)—the results are usually reported as a number with an arbitrary unit of measure (abbreviated as a "U" on the report, for example). A positive result from this method will be a number of units that is above the laboratory's reference number (cutoff) for the lowest possible value that is considered positive.

Patterns of cellular fluorescence
In addition to a titer, positive results on IFA will include a description of the particular type of fluorescent pattern seen. Different patterns have been associated with different autoimmune disorders, although some overlap may occur. Some of the more common patterns include:

Homogenous (diffuse)—associated with SLE, mixed connective tissue disease, and drug-induced lupus

Speckled—associated with SLE, Sjögren syndrome, scleroderma, polymyositis, rheumatoid arthritis, and mixed connective tissue disease

Nucleolar—associated with scleroderma and polymyositis

Centromere pattern (peripheral)—associated with scleroderma and CREST (Calcinosis, Raynaud syndrome, Esophageal dysmotility, Sclerodactyly, Telangiectasia)

An example of a positive result using the IFA method would give the dilution titer and a description of the pattern, such as "Positive at 1:320 dilution with a homogenous pattern."