elcamino,
From what I understand, the majority of people diagnosed with AS have negative results on the rheumatoid factor. Did you have a chance to read through those websites I posted above? Look in Key Points, third paragraph:
http://www.ccjm.org/PDFFILES/Brent304.pdf
It looks to me as if AS can occur in many of the same areas as RA, so a misdiagnosis could be possible, in my opinion. See the next site and click on the diagram. AS and the spondyloarthropathies usually affect the spine, but "other areas of the body can also be involved. Spondylitis does not follow the same course in everyone." (I can't get the direct link to work, so click on "about Spondylitis", then "Complications of Spondylitis")
http://www.spondylitis.org/main.aspx
Also, that website, Spondylitis Association of America is a very comprehensive, EXCELLENT site. Many of the topics can be accessed without paying or becoming a member. http://www.spondylitis.org/main.aspx
Their message board is also good: http://bbs.spondylitis.org/cgi-bin/ultimatebb.cgi
Regarding Enbrel for Crohn's, I've only read one article on PubMed that showed Enbrel had some benefit for Crohn's patients.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=Abstract&list_uids=11569676&query_hl=1&itool=pubmed_DocSum
All other articles I've seen indicate that Enbrel works for the arthritis symptoms in Crohn's patients, but not the digestive symptoms:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=Abstract&list_uids=12480676&query_hl=1&itool=pubmed_DocSum
There's even one that suggests that Enbrel "may have contributed to the development of clinically significant inflammatory bowel disease."
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=Abstract&list_uids=15801037&query_hl=1&itool=pubmed_docsum
Go figure!!
Oh, by the way, I had a remarkable response to my first Enbrel injection in December 2004. My previous rheumatologist, who first prescribed it, didn't believe me when I told him I noticed a difference within three days. After one month, my ESR had gone from 46 to 6. Our insurance plan was switched (not by choice!) in 2005, so I had to find all new docs - GI, rheumatologist, ophthamologist, GP, what a pain in the neck, literally!
My current GI suggested once that Enbrel may be benefitting my questionable IBD. My last ileo-colonoscopy in Nov' 05 showed no abnormalities macroscopically or microscopically. His other theory is that my so-called IBD could be the result of the nsaids I was using for my inflammatory arthritis at the time of my first bowel flare (diagnosed by my previous GI doc as moderate-severe UC in January 2003, even though the pathologist report suggested Crohns, due to granulomas, chronicity, and the patchy nature of inflammation.) The following study was submitted by my current GI doc, who believes the use of nsaids can cause damage to the small intestine and/or the colon.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=Abstract&list_uids=15017486&query_hl=46&itool=pubmed_docsum
In another post you mentioned a similar situation, so maybe your GI doc has been conversing with mine...!!
So I have no answers for any of this, only never-ending questions and continued searches for bits and pieces of the giant PUZZLE, as I continue to inject my treasured Enbrel and enjoy relatively good health.
Good luck to you, elcamino.
Jan
Current dx: seronegative rheumatoid arthritis first diagnosed in 1991,
(or a spondyloarthropathy, tested HLA-B27 positive in 2004)
recurrent iritis, one episode of papillitis, Raynaud's,
questionable IBD (UC, Crohn's or none)
Current prescriptions: Enbrel
Past prescriptions: plaquenil, naproxen, relafen, piroxicam, vioxx, imuran, methotrexate, entocort, asacol, prednisone, flagyl