Normal Values:

Usually, there is no detectable ANA in the blood (negative test). Sometimes, however, people who do not have any specific disease may have low levels of ANA for no obvious reason.

ANA is reported as a "titer." Low titers are in the range of 1:40 to 1:60. A positive ANA is much more significant if you also have antibodies against the double-stranded form of DNA.

ANA does not confirm a diagnosis of systemic lupus erythematosis (SLE). However, a lack of ANA makes that diagnosis much less likely.

Although the ANA is most often identified with SLE, a positive ANA can also be a sign of other autoimmune diseases.

Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.

What abnormal results mean:

The presence of ANA in the blood may be due to:

• Chronic liver disease
• Collagen vascular disease
• Drug-induced lupus erythematosus
• Myositis (inflammatory muscle disease)
• Rheumatoid arthritis
• Sjogren syndrome
• Systemic lupus erythematosus

Increased ANA levels may sometimes be seen in people with:

• Systemic sclerosis (scleroderma)
• Thyroid disease