Does anyone know if synthroid can cause a false positive in modulating? Has anyone had a positive in all 3 groups? or more than one at one time?
Thanks,
Mike

Mike, I could find absolutely no findings on that. Perhaps Mrs. D. might know more.

MG is a clinical diagnosis that is confirmed with testing. So if someone has all the obvious signs of fatigable weakness plus positive test results, chances are that they have MG.

Yes, some Acetylcholine Receptor Antibodies are positive (false or not) in ALS, in older patients, in some patients with Downs Syndrome, patients taking D-Penicillamine, etc. That is why a good doctor will take the sum of all the evidence before declaring someone has MG.

The three antibodies - binding, modulating and blocking - are not necessarily positive in all MG patients. Some only have binding, some only modulating and some have both.

http://neuromuscular.wustl.edu/mtime/mgdx.html

Antibody titers vary greatly, even for one person. It depends upon what meds you are on, how bad the MG is, etc. Even then, some patients who have severe MG, for example, may have a low titer while someone who is mild may have a high one. MG experts do not go by a ACh antibody test to decide how an MG patient is doing because it's highly variable. A clinical exam, breathing tests and various other tests like arterial blood gases is how a doctor determines how a patient is doing.

Is there a reason you are asking?

Annie

Thanks Annie
I'm posting for my sister. Her Modulating came back positive. Our mom and 2 aunts were DX'ed and of course I was dx'ed (positive binding). She needs to get over her shyness. She has a Dr appt in the morning. I think her doc sent off more bloodwork last visit. Her symptoms below.
1. droopy eye brow
2. one side of face drooping (I think)
3. weakness in legs
4. one arm so weak she can't lift milk out of frig.
5. at times severe tirdness
Mike

Aw, Mike, shyness is sort of cute.

Does anyone else out there have modulating only antibodies, besides Mike's sister and me? 3 - 4% of MGers only have those. I think it's funny how they say 3 - 4 percent. Why don't they get crazy specific and say 3.2 - 4.3 or something. That number is probably higher.

I hope her appt. goes well. Drooping muscles are not normal, neither are weak ones. If she gets worse upon exertion, that's typical of MG. The more you do, the more acetylcholine you need. In MG, not enough acetylcholine gets to the muscles because the "doorway" that it goes through (from the nerve to the muscle) is either blocked by antibodies or destroyed by them.

Let us know how it goes. Or maybe she can!


Annie

I'm on pins and needles till tomorrow. I'm sure as this plays out she will get over that shyness because this board makes you feel like you aren't fighting this alone.
Hugs
Mike

My sisters last visit the Dr did RNS test and the Dr said the results were "abnormal" what the @@@@ does that mean? Her Dr wants single fiber test done at Duke but next available is March. My sisters Dr sent blood work off to Mayo the last batch wasn't sent to Mayo. The local lab thought they could do it. The Dr also set up CT of her Thymus on Tues. also promised meds next visit.

Another development is my sister says she has a photo of our Grandfather in his later years with a droopy eye lid. This saga keeps getting really strange.
Mike