Good question Ellenmelon!
Basically, although both are considered autoimmune diseases, and both involve incredible fatigue and malaise, there are major differences.
Fibromyalgia (the name means sore fibrous tissues) involves pain in the muscles and, perhaps, tendons. It is sometimes misdiagnosed as tendonitis at the beginning. Fever is not usually a component. There is no progressive destruction of either muscles or joints, although there may be progressive pain. There are 18 points on the body that usually exhibit some tenderness. The diagnostic criteria for fibromyalgia includes the presence of at least 11 of the tender points. BUT, not every person with fibromyalgia has a full 11 tender points at any one time. They tend to come and go. I've been tracking my tender points in an attempt to figure out how it flares and ebbs. Some days I've had the full 18 tender points! But other days I've only had 1 or 2. Those are the good days!
RA does involve progressive deterioration - of the joints and the tissues that line the joints (the synovial membranes). So fibromyalgia is more muscle (although joints may ache some, too), and RA is more joint (although muscles may ache a good bit, too). Fibromyalgia does
NOT involve destruction of tissues, and RA
DOES involve destruction of the tissues of the joints. The fatigue involved with RA is much more intense (especially during flares), but rest is restorative, while rest does not relieve the fatigue associated with fibro.
Although pain may interrupt sleep in RA, there is no associated sleep disorder as there is in fibro.
Fibromyalgia seems to be present in a percentage of RA patients. Whether there is a causative association between them is not known at this time. I find this very interesting, however. I have had 4 diagnosed autoimmune conditions, now. Pseudotumor of the orbit, a flaring and remitting course of thrombophlebitis, fibromyalgia and RA. Autoimmune diseases seem to "run in my family," and autoimmune diseases are thought to have a genetic component.
I am rather grateful that I developed the fibro before I developed RA. I have learned to function despite pain and fatigue, so I am able to apply many of the same coping mechanisms I have used for many years with the fibro.
The pain and stiffness of the RA are much "worse" than fibro, and are different in that they are more focused in one or two places in my body. For instance, my hands are more affected, and I'm aware of severe, deep pain inside the main joints - the MCPs (the big knuckles where the fingers join the hand) and the PIPs (the knuckles between the MCPs and the end finger joints). The DIPs (the end knuckles of the fingers) are somewhat less affected. While there is symmetrical pain (both hands) one hand is usually worse than the other. Being right handed, of course, my right hand is "worse!" Wouldn't you know it! The same goes for feet - my right foot hurts more, but both feet are involved. The right knee is more swollen, tender and stiff than the left, but both knees are involved.
This is typical. But there are non-typical presentations, in which only one or two joints are involved.
Although there most often is a positive RA-factor and elevated C-reactive Protein (CRP) and Sedimentation rate (SED Rate) in RA, it is possible to have RA with negative blood work. This is called "sero-negative" RA. Many MDs don't recognize this as RA, and will treat it as "just some arthritis." More are beginning to recognize that lab work is not the final answer, however. It is the entire clinical picture. Swollen, painful joints, often low-grade afternoon fevers, and fatigue should raise suspicion that RA is present.
Please remember, though, your own doctor is the final authority when it comes to diagnosing and treating RA. If you think you may have RA, and your MD doesn't, you may want to seek a 2nd opinion from a rheumatologist. But just as all Family Practitioners are not equal, and all Internists are not equal, all Rheumatologists are not equal. There is a good reason to see a "board-certified" rheumatologist - this is a person who has had a long residency in internal medicine, specialized in the autoimmune diseases, and has been tested and certified by the American Board of internal Medicine AND has a subspecialty certification in rheumatology. This will not assure you get a doc with a wonderful bedside manner, but ensres that the doc has the knowledge - the book learning - to practice in the specialty. I hae been to 3 rheumatologists in the past 30 years. Two were great, one was an unmitigated disaster. You have to find the doc that will work best for you. The one that was a disaster for me has one of the largest practices in Atlanta, and his patients sing his praises. I can't stand him. I like the first one I went to the best, but he has since retired and died. I'm going to his son and daughter-in-law (both board-certified in rheumatology) and they are very good, compatible with my needs, and I like them very much. So I encourage people to find good, well-qualified docs that they can work with.
Well, I've gone on and on, here. I'm studying this so I can understand my own diseases, and am glad to share what I learn.
Hope this has helped some!
Cheerio!
Elizabeth
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~*~ Don't be discouraged. It's often the last key in the bunch that opens the lock. ~*~
~*~ Author Unknown ~*~
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