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Rheumatoid Arthritis

Rheumatoid arthritis is a "chronic inflammatory, multi-system illness, involving primarily the joints with a history of exacerbations and remissions.'' It is a multi-system disorder. When we look at someone with arthritis I like to remind people again of the differential diagnosis of various forms of arthritis. Acute monoarticular arthritis, differentials including in front of you, but the main things that we talked about before, trauma, crystal disease and bacterial diseases in septic arthritis. But thereís a whole host of other things that can cause a monoarticular arthritis. Acute polyarticular arthritis. Infection-related types of arthritis, occasionally sepsis. Very unusual to have a polyarticular arthritic.

We talked before about that polyarticular presentation that would eventually settle into a joint. Lyme disease can present as polyarticular disease, so again itís more commonly monoarticular. Rheumatic fever, HIV and other viral infections can cause arthritides. Non-infectious causes; again, a whole host of rheumatologic diseases, vasculitides, sarcoid.

So there is a whole differential whenever we have people who present with arthritis and because of this, how to help differentiate the different kinds of arthritis, the American College of Rheumatology came up with these criteria for RA. And these are the criteria that have been most recently adopted by the ACR and it requires four of the following: a.m. stiffness lasting more than an hour, swelling in three or more joints - and when we are talking about joints, two MCP joints actually counts as one joint so you should think of it more as joint regions - swelling in hand joints.

Rheumatoid factors - we talked about these - are identical things that we talked about the other day. A whole host of reasons people can have positive rheumatoid factors.

Rheumatoid arthritis, believe it or not, seems to be a fairly new disease in our history. We donít have any real skeletal evidence of rheumatoid arthritis from ancient times, like we do ankylosing spondylitis, various degenerative processes. Weíve got skeletal remains from Egyptian times for things like ankylosing spondylitis.

Incidence of RA is a lot harder to identify and some of the best places, the best sources, for determining the incidence of RA have been like at the Rochester Epidemiologic Project. If you look at a lot of these epidemiologic studies and various journals, they all say "From the population of Ohlmstead County." Iím sure youíve all seen that a number of times. They have a very wonderful database because of the limited number of places you can get medical care in that county where the Mayo Clinic is. All of their database is from doctors offices and the hospital, who are all computerized in the central system, and so if someone wants to go back and research those patients they are able to dig through the patientís entire history and try and make sense of it. So you have the most complete data we have anywhere, longitudinally. From their database, which is primarily a Caucasian database.

Again, genetics has been looked at extensively and we are learning more and more about the genetics. These genes that I learned about in medical school as being predisposing to certain things or being a higher incidence in certain diseases, we are actually now finding out what they are. Many of these code for the particular part of the protein on the MHC molecules. So it has a lot to do with the way our immune system interacts with itself.

A thing that has become much more apparent, and seemingly more important over the past couple of decades, is to understand this problem; morbidity and mortality in RA. It used to be thought years ago that RA was a pretty benign disease and that if people were followed over a period of time, in a significant percentage of them it just sort of went away and most people had fairly well controlled RA with very moderate treatment. We are not finding that to be true. Certainly we know that certain things are predictors of higher morbidity and mortality.

Another thing I wanted to point out is that sometimes in older men, they donít seem to have really really pronounced synovitis but they do have a lot of stiffness and the NSAIDís arenít very helpful. Most of these people just require low dose steroids and they do very well.

Well, the diagnosis of the rheumatoid arthritis; we talked about the criteria a little bit ago. Again, history and physical. You look for the symmetric polyarthritis that has been present for six weeks or longer. Tenderness, swelling, warmth, decreased range of motion, etc. Look for rheumatoid nodules. Occasionally youíll see low grade fevers. In the laboratory evaluation often you will see anemia, it is not uncommon for patients with RA to have hemoglobins of 9 and 10. They very often have an elevated ESR and this does tend to correlate to some degree with their activity of disease. Rheumatoid factor positivity between 60-90%. Synovial fluid though, I donít tend to do a lot of synovial fluid analyses on people who present with diffuse polyarticular arthritis. It is classically a class II fluid. One of those things I remember back from residency days, like the pleural fluid in rheumatoid arthritis, patients tend to have real low glucose and you always had to remember to distinguish that between septic empyemas. Likewise in rheumatoid arthritis joints, people tend to have very low glucose as well. X-ray findings, periarticular osteopenia, the loss of cortical white line. If you look very closely at the outline of say the distal end of the metacarpal bones, they tend to have this little white line around the edge of the bone and that tends to disappear, and for a really sharp radiologist itís an early sign of RA. Certainly soft tissue swelling, joint space narrowing and eventually erosive disease are potential findings. There is our RA criteria again, just to remind again, these are criteria that are helpful to you to identify them. You donít live and die by them, but the key thing is remember six weeks or longer.

There is a significant differential diagnosis. Thatís why I put the criteria up again. Thereís a lot of other etiologies. Always consider seronegative spondyloarthropathies and other rheumatic diseases, but occasionally we get fooled by other disorders; gout, spontaneous bacterial endocarditis, sarcoid, thyroid disease. Remember that from the other day. Iím going to say it again, thyroid disease. Interestingly enough, steroid withdrawal. How many of you have seen patients with sort of pseudo-rheumatism from steroid withdrawal? A number of you. I think itís important to distinguish what this steroid withdrawal typically causes. If we are going to blame this on steroids, have some sort of concept of what steroid withdrawal can do. Almost anybody who is on a significant dose of steroids for a period of time, when you lower their steroids they can have this pseudo-rheumatism. These joint aches and pains. The key thing is that when you reduce their steroids it shouldnít be something that lasts three weeks from the steroid withdrawal. Classically, that will go away or abate after three to five to seven days. So sometimes when you have those patients that you are really struggling to taper their steroids and they have that little bit of increased activity, if you can get them to sit tight for a few days it may help you to distinguish between steroid withdrawal and actual exacerbation of their underlying symptoms. A lot of our patients, particularly RA patients, are very sensitive to the steroid decreases and unfortunately our reflex, when something gets a little more symptomatic, is to kick them right back up.

RA is a disease that has obviously many bouts. They tend to have exacerbations, remissions, almost any joint of the body can be involved. Weíll go sort of head to toe and talk about various joints. First of all, we saw some pictures of the cervical spine on Monday and the big concern is the atlantoaxial subluxation or instability due to active synovitis. When that happens people will often develop various neurologic symptoms. Usually this sort of dysesthesia that radiates down their spine, but they can develop a number of other problems, from frank spinal cord symptoms of incontinence, or spinal cord compression signs of sensorimotor abnormalities, to these more vague things like, "Gosh my head just feels like itís coming off." Or, "I just donít feel like myself."