There is a thread in the sticky posts at the top of this board that discusses the lab tests for Lupus diagnosis that addresses ANA testing. Also look for a link in that thread as it has some of the best info on Lupus. I am sure there is plenty of info there.
jtc4, hi & welcome. I'm only a patient, so here's my only-a-patient understanding of the basic about ANA. First, it's tricky. I've read it can be low-positive in people without any disease (due to family tendency, a passing virus, etc.) Also, it's positive in a variety of conditions within rheumatology, AND in other branches of medicine, too---so it's a "general" sort of test. Meaning, positive ANA does not prove lupus... more like, when accompanid by symptoms, it suggests the need for further tests & refinement.
I think somewhere I read that rheumatologists may each have their own "worry level". I think one article, authored by a rheumie, said he personally takes 1:1280 seriously, when coupled with at least some symptoms &/or other markers.
I think there are two different measuring systems for ANA. One is based on titres doubling, like 1:60, 1: 320, 1:640, 1:1280, etc. In that system, some rheumie/authors I've read have written that 1:1280 should raise a red flag.
In the other measuring system, I think I've read that 1:40 shoukd raise a red flag.
BUT in both ANA measurements, I think OTHER signs & symptoms are SUPPOSED to count equally. Meaning, no matter what your ANA is at any one point, your life history and other tests should count, meaning ANA alone shouldn't be the only thing considered. But I'm only a patient, of course! Best wishes, Vee
If you have a positive ANA but no positive antigens (DsDna, SM, RNP, etc), and no symptoms, then likely there is no reason to worry. However, if you have a positive ANA at 1:320 and symptoms, but nothing else showing up in your blood work, an autoimmune issue could be developing. Personally, I don't think high titers should be ignored.
I had a positive 1:320 homogeneous when I first got sick. Now I have a positive ANA with a high RNP 13 years later. It must be speckled now but the test didn't say. However an RNP is of a speckled pattern.
There are other tests doctors do also that help in the diagnosis. Like ESR, CRP, CPK, RF. If nothing shows up here, I'd say your ANA test may be ignored unless you have a positive antigen, because without the antigen, they can just say, well maybe your ANA is a false positive. Or if the ANA becomes negative at any point and time (though that can mean disease is in remission also), it can be ignored. I have no idea what would show now with me with the CRP and such, but all that used to be normal for me and it did not help in as far as showing how sick I was, not at all.
Yes if your swelling, I'd ask my doctor for an ANA. It could be related to a connective tissue disease. I wouldn't ignore such a symptom.