Anti TPO is correct, either you have the antibody or you don't..if you do then you have hashimoto but does not necessarily mean you need thyroid replacement...you can keep the antibodies down by examining your diet and removing anything that is creating inflammation in your body. I stay off gluten and my antibodies stay down. I am not sure you can ever get rid of the antibody once you have it...I could be wrong..could be something I don't know or have heard of yet. lol
The biggest problem with Hashi is the swing from hyper to hypo that your body will go through..it's awful. Stabilizing effect on this is io, at least it has been for me..I will add that even staying gluten free does not help my thyroid stop me from going through that roller coaster, only the IO has helped in that regard. Oh what I believe is keeping me off meds for now is being GF and sup'ing with IO.