No, an ANA by itself does not indicate any disease, nor does it indicate any active disease. Here is what Johns Hopkins (Maryland, USA) has to say about
a positive ANA.
"A positive ANA result means that you have a higher than normal concentration of these antibodies. This is one of the tools in diagnosing lupus as well as several other autoimmune diseases, so a positive result may be related to lupus or to another disease. Or you may simply have a higher than normal concentration of these auto-antibodies that may not have any impact on your health. Even among people with lupus, ANA results can vary widely; one person can be in remission at a certain titer of ANA while another can be extremely ill at the same titer. Autoimmune diseases often have a systemic effect on the body and are very complex by nature. Your healthcare provider will interpret what the test results mean for you and may need to compare your test results as well as the severity of your symptoms over a period of time in order to make a definitive diagnosis."
If you have already been diagnosed with Lupus, active disease is generally characterized by symptoms and by the blood's inflammation markers. You need to be under the care of a rheumatologist -- a PCP is not trained or experienced in the treatment of Lupus or other auto-immune diseases.
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2000DIAGNOSING LUPUS & HW's LUPUS 101
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