Hello I have sle lupus and there really isn't much that they can do to determin it outside of evaluating your symptoms and bood work they will test your ana which is done through blood, and maybe your kidney function which is also done through blood and urin sample. Then they look over all the symptoms you have, it is possible to have lupus and have a negitive ana test here are some places to look for more info on lupus testing.

Http://www.Labtestsonline.Org/understandin g/analytes/ana/test.Html

http://www.Labtestsonline.Org/understandin g/analytes/ana/faq.Html

http://www.Uklupus.Co.Uk/ana.Html

the last link is about lupus testing and diagnosis, if your doctor hasn't ordered an ana test yet I would advise you to request it it's a first step in diagnosing it.

Hope that helps please keep me posted