Hi all I had some pain and swelling at joints and had ASO,CRP and RF tests done. ASO and CRP results are okay. RF came out to be 52 IU/L Limits (0-20). Is this something to worry about? I recall that my RF was high at another test performed about 5 years ago. Is RF something that comes up to be high for CFS patients.I am wondering if I should have further tests or visit a rheumatologist which is quite difficult for me due to exhaustion.If this result is not something to worry much about,I won't bother with further tests. What do you think? Thanks.