I just want to say that in my totally amateur opinion--I'm just another MG patient who likes to read about the disease--it sure sounds like MG is a big possibility. The hallmark of MG is the fatiguability you describe. I went through something similar: a big work-up with all these experts, and their consensus was "we're baffled." I tested negative for the antibodies (three times). My first two SFEMGs were non-conclusive.

In the end, after 15 months, I got a diagnosis from a different neurologist that my own neurologists sent me to. Try to see if they'll refer you to a neuro-ophthalmologist! Many of us have gotten answers there that we couldn't get anywhere else. Ask them if there's an MG expert you can see--you may have to travel. If they can't give you a diagnosis, they should be able to recommend someone who can.

Here's another thing: the IVIG trial is a good idea. If it works, it will at least show that you have an autoimmune disease. The treatments for MG (Imuran, Cellcept, Prednisone, etc.) are also used for other autoimmune diseases. I have this half-rational fear of coming down with rheumatoid arthritis (hey, is it normal for my age (46) to start getting lumpy finger-joints?) and it's reassuring to know that the treatment for RA is the same as the treatment I'm already getting for MG. Just remember that, like the typical MG patient, being cold makes you better and being warm makes you worse. If you have a SFEMG, make sure you're warm for it.

One more thing to keep in mind: if you do have IVIG, and if it only gives you a small improvement--one that doesn't quite convince you it's working--don't hesitate to try it twice. Many of us didn't get great results for the first one or two, but then got really dramatic results for the second or third time.

Abby