It's really hard to distinguish between one kind of joint pain and another. One way to tell the difference seems to be to test and see if the pain responds to certain medications. Some meds seem to help arthritis pain more, some help Lupus-induced pain more.
But, in general both arthritis and Lupus produce inflammation, and it's the inflammation that in turn produces pain. Sometimes if you visit the Dr while you have pain, a blood test can give them more information as to what is going on.
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2000DIAGNOSING LUPUS & HW's LUPUS 101
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