The presence of antinuclear antibodies is a positive test result. But having a positive result doesn't mean you have a disease. Many people with no disease have positive ANA tests — particularly women older than 65.
Mononucleosis and other chronic infectious diseases have been associated with the development of antinuclear antibodies. Some blood pressure lowering drugs and certain anti-seizure medications may trigger antinuclear antibody formation, as well.
If your doctor suspects you have an autoimmune disease, he or she is likely to order a number of tests. The result of your ANA test is one piece of information your doctor can use to help determine the cause of your signs and symptoms.