istone, the best I can do is share with you what I've learned through my own experience and from reading what others have said.
Spondylitis, in it's early stages, consists primarily of soft tissue inflammation. The nature of this is not consistent and so migratory pain is common as the inflammation in one area subsides and another area increases.
I have chronic tendonitis in my right shoulder, both knees and both Achilles' tendons. Also, I've had chronic inflammation in the Synovium, the tissue which makes up the capsule around the joint, in my knees and the same tissue is sclerosing, or hardening in the joints of my lumbar spine. My pain comes from my R shoulder, neck, thoracic spine, lumbar spine, R SI joint, both hips, both knees and both ankles. Sometimes my fingers get in on it too, but not too often. The back, neck and SI joint pain is almost constant now, but the rest varies in intensity and and occasionally come and go.
One result of the inflammation is muscle spasms and I live with those with the help of a muscle relaxant called Zanaflex (tizanidine). these spasms make everything stiff and I long for the day that I can be spasm free.
I am also HLA-B27 negative and I've never had an elevated ESR or CRP. The role of HLA-B27 is not well understood and testing for it does not make much of a difference in terms of being Dx with Spondy. Yes, many more people who test positive will be Dx, but having a positive test does not mean that you will get the disease, just that you are at a higher risk for it. Likewise, there are many people who test negative and do develop the disease. It is suspected that although B27 does play a role, there are many other genes that contribute.
Many people with Spondy respond well to NSAIDS, especially in the early stages of the disease. Since I also have Crohn's disease, I can't tolerate them, but they may work well enough for you, at least for now. I have read some info about the possiblilty that NSAIDS may actually provide temporary relief, but in the end, lead to disease progression. This is not the general consensus, but I thought you should know of the possibility. I think that whether you choose to use NSAIDS, is something you need to discuss with a Rheumy. The truth is, if I could handle NSAIDS, I would take them.
Since Spondy is an autoimmune disease, immunosuppressants seem to offer the most hope to control disease activity. The meds most often used to treat SpA are Methotrexate, Enbrel, Humira and Remicade. IMO, Remicade is the least toxic and that is what I chose to begin treatment with. Now, that things are worse, both from the SpA and Crohn's, I'm upgrading to Humira, which will treat both disease. Enbrel was not strong enough to affect the Crohn's.
SpA id made up of a group of different diseases that are mostly considered to be autoimmune. Reactive Arthritis is among them and so it's possible that gut trouble or some type of infection could have triggered the arthritic condition. IMO, those most at risk for and AI disease would likely develop SpA at some point, whether or not there was some thing to call the precipitating cause, such as an infection.
SpA or AS does not often show on X-rays or even MRIs until the disease process is considerably advanced. The earliest imaging which might indicate it would be a bone scan.
There is no diet proven to help, but many people with SpA insist that a carb free diet has helped them considerably. I do not have the wear-with-all to stick to something like that.
I hope you can get some answers and relief soon.