It never hurts to run these things past your rheumy, especially if you have the symptoms. Just remember that there is no single test that will confirm or rule out lupus. It's a combination of a bunch of things. Lupus is the "great mimicker". Your chron's will present many of the same symptoms as lupus. Any blood tests will also show activity of something autoimmune, but it could just be your chron's. You'd get the same results back for either disease.
One set of blood tests you could ask for are the anticardiolipin antibody and antiphospholipid antibody tests. Those two are very specific to lupus. Both are blood clotting indicators. In many people with lupus, the disease will produce a protein that causes the blood to get thick and sticky. I"m not entirely sure if these tests are common in chron's.
Testing for lupus can take you down a long and winding road of frustration. If you're going to go there, just be prepared!
I can do anything through Jesus Christ who strengthens me. I have learned in whatever state I am in,to be content. Phillipians 4:11-13
34 years old. Diagnosed with lupus in 2000. Fibromyalgia, anti-phospholipid syndrome(APS)(stroke),Sjogren's, Raynaud's, seizure disorder-(miraclulously disappeared!), Libman Sach's Endocarditis, vasculitis, sacroiliitis, arthritis (neck) . Prednisone, Imuran, Coumadin, Clobazam, Amitriptyline, didrocal, Cozaar, Tramacet, calcium, Cykolokapron, multi-vitamin, vitamin D, Magnesium, vitamin B6, Acidophilus