I said often, I did not say exclusively in psoriasis patients. And there was never a rheumatoid factor test. Your doctor may call it that, but they are testing for the inflammatory markers. I have RA and have been on Humira for it for a couple years now. And I wasn’t talking about how to diagnose, I was adding to the point that you can show negative but still be diagnosed with something. And that it has an actual name, not just a misdiagnosis for another form of arthritis.

Psoriatic is often in conjunction with psoriasis. With RA they aren’t testing for a rheumatoid factor. They test for inflammatory markers. And it is possible to be diagnosed with RA without having any inflammatory markers. It is called seronegative RA.