Thanks for the quick reply, rumpled. I underwent a battery of tests, including a couple of EMGs, when I was convinced I had ALS, and everything was clear (in fact, I remember one blood test came back so normal that it was remarked upon by the doctor as being too good!) I don't believe I had specific tests for the MG or LEMs antibodies, though it was a neurologist who ordered the blood test (about 8 years ago) so perhaps he asked the lab to check for those antibodies (were they were able to back in 2000?).

I thought about MG -- but have never had any noticeable eye muscle weakness so, after eight years, I thought that pretty much would rule it out. Is that right? I have never heard of LEMs -- just looked it up. Wow, that's a scary one, but fortunately it doesn't seem to fit in my case -- the weakness in LEMs is proximal, i.e. thighs and hips, not fingers and ankles and fasciculations seem to be specifically ruled out as a symptom of LEMs.

If you can have MG without any eye mucle weakness presenting, then that's the best fit I can come up with. Since I really haven't been obsessing about it (since knowing it was not ALS) then I haven't been worrying getting a diagnosis. But the brisk walk and the attendant muscle weakness I had last week had me thinking about it again, which is why I posted this question.