Caligirl, If you go through the research you can find online, you will also see that there have been cases of people who have sero-negative SLE. It is said to be uncommon, but in reality, if it's not being diagnosed or people are not believed, I have to wonder if the statistics are accurate.
Educating and advocating are two of the biggest takeaways from this--and neither one is easy--particularly the latter. Where I live there are only two practices available and they are an hour from where I live. When the first Dr. refused to believe me despite some positive tests, a strong familial link, and very definite symptoms, I contacted the other office and was told that the first available appointment would be 18 months out. I asked about a waiting list and the woman sort of chuckled because that list was so enormous. I *had* no choice but to go back to my regular rheumy and I tried very respectfully presenting him with all the paperwork I'd collected- and since he'd told me the first time that I had "too much hair to have lupus", I showed him the hair had that either broken off or been pulled off in brushing for less than a week. He became offended and said that he was sorry I didn't believe he cared for his patients, which was not my point at all.
I believe he was at the point of dismissing me from the practice from disagreeing with him. Luckily, there was a weekend and on Monday he wrote me an email stating he was sorry for "flying off the handle" at me. I told him that I no longer wanted to take the chemo regimen they had changed me to, as I didn't feel it was doing me any good. I asked to be put back on the Plaquenil and Prednisone that I had been on when I came to him, 10 years before.
Last month for the first time, my liver functions, chemistries and CRP were all in line! He still won't admit it to me, slowly I think he's coming around.
Whatever you do, don't give up on researching and advocating until or unless you are definitively proven wrong! Best of luck!