Sophie, there are two parts to an ANA test.

The first is the titre (the level of anti-nuclear antibodies in the blood). This is measured using an ELISA (an immunoassay) - the titre is expressed as a ratio (1:160, 1:320, etc). The higher the titre the more anti-nuclear antibodies are present in the blood.

The second is the staining pattern - which parts of a nucleus the anti-nuclear antibodies react with.

Many people with no other signs of an auto-immune disease have an unusually high ANA titre. For that reason an ANA test is regarded as confirmatory rather than diagnostic.

This is discussed from a clinical perspective here http://www.racgp.org.au/afp/2013/oct...antibody-test/.

hi Echoes

I didn't know that the ANA can go back and forth between negative and positive. THis was my first ANA test in awhile and it came back negative. Years ago, when I had Lyme disease, my ANAbwas positive.

Thank you Kiwi..this information was very helpful and I got my answer!!!!

Dear Sophie:

All my life I've had autoimmune-like conditions without EVER testing positive of an autoimmune condition.

Then I was found to have Primary Immune Deficiency Disease.

I asked my brilliant Immunologist, how I could have all these disorders, Sjogren's -like, Interstitial Cystitis, PN, SFN, etc.?? She said: "Your Immune System is attacking you with biochemicals that are NOT autoantibodies. Your Immune System is using something else to attack you, probably cytokines but we don't know."

My Husband is a research Immunologist (go figure!) and my Immunologist and he have great discussions about what it might be that is destroying my organs/systems (Now my lungs are damaged).

Hang in there, we are on the frontier of Immune Disorders. Find the very best doctors you can, preferably in a research center.

There aren't easy answers, and we have a long way to go....but you have company on the ride!

Hugs, ElaineD