...is high ,? knee enfussion, 50 cc drained, no relief from cortisone, clean xray of knees, mri shows only obvious swelling. Ran blood tests. Cbc is all good, with a negitive ana test, normal range for ra but sed rate is high . I am worried. what does this mean. Knee is still got fluid,and swelling but have regained some range of motion. Still feels like there is something in the middle of my knee. Do I have to be worried about an autoimmune disease or is the high sed rate just due to knee swelling ?