Hi Maria
I am anti CPP positive too, I found out the same way as you - from a letter to my GP from my Rheumy (The Rheumy did the test the first time he saw me). The Rheum didnt tell me he was doing this test, just thought it was a standard blood test, and the result and meaning of it wasnt explained to me either, I found out from NRAS. Jenni has it right in her reply.
lizzie