Hi Mari Mari,
I also tested negative for RA, but have all the syptoms, and my Rheumatologist told me that was common, happens 50% of the time. At first I was scheptical too, but I started to research, and found out it does happen. I clearly have inflamation that she can see, so she does believe me, and has started me on medications. I have started the Doxycyline 2x a day, and am waiting for that to kick in. Should take about 3 months. I am also on 10mg of predison until it does kick in, which i dont like, but I tried to go off it, and my inflamation came back even worse. So I went back on it. I started the Doxy. cause it had mild side effects, and seems to work on many patients, from what I have read. Here is a good website that explains the seronegative.
http://chroniccurve.tumblr.com/post/15295991395/seronegativity-for-dummies-a-lesson-in-seronegative
Lisa