I was wondering...is it possible to have a normal ANA at one lab draw and then abnormal at the next? I know the first one they drew was normal, but she drew it again and that is when they found that I was + for RF. They could not find the results of my ANA at that time, but the fact that she drew it again made me wonder if it could be normal or negative at one time and then positive or abnormal at the next. Does anyone know?

Thanks,