OK, that helps. Anti smith antibodies are a type ANA (antinuclear antibodies) that are very specific for lupus. While they are not present in all lupus patients, 99% of those with a positive result have lupus. The level doesn't matter as much. It does not reflect disease activity, so it is not helpful for monitoring treatment efficacy.
http://www.hopkinslupus.org/lu...s/lupus-blood-tests/Lupus is a very difficult disease to diagnose, so I can see why they are following you on this. So, while having a positive result for anti smith antibodies is very suggestive of lupus, there is no blood test that confirms a lupus diagnosis. You also need to have the clinical signs and symptoms, which vary from person to person. In addition, it can take years to fully manifest. It is possible that you have inflammatory arthritis along with osteoarthritis. I know that can happen, because it is true for me, but no lupus (so far). That is why I am on Simponi.
http://www.hopkinslupus.org/lu...fo/diagnosing-lupus/Jan