Question
What do you think of ELISA testing for ANA as opposed to IFA testing?
Answer
For those not familiar, many if not all of the larger commercial labs have switched theier ANA testing to ELISA systems. In my expereince there is a difference between the older IFA (immunofluoresce) testing and ELISA– some patients are positive only on one of the assays. I could see how ELISA might be more reproducible, but I would still favor IFA. The future will likely be all ELISA.
