ugh, how frustrating!!! Who diagnosed you in the past - can you go back to them? The mestinon helps you? Why can't they just leave you on it if it helps - regardless of your diagnosis ? My neuro is so close minded it's frustrating - a negative test means you don't have it period - they don't think outside of the box - they dont' even consider seronegative diagnosis.. so incredibly frustrating.. keep us updated!