MG and CIDP overlap

Sorry, I am unfamiliar with MG and it does not show up on an internet search. Could you please explain what MG stands for ?

Thanks.

MG = Myasthenia Gravis
What is myasthenia gravis (MG)?

Myasthenia gravis (meye-uhss-THEEN-ee-uh GRAV uhss) (MG) is an autoimmune disease that weakens the muscles. The name comes from Greek and Latin words meaning “grave muscle weakness.” But most cases of MG are not as “grave” as the name implies. In fact, most people with MG can expect to live normal lives.

When you have MG, your muscles weaken with activity. Muscle strength returns with rest. MG usually affects the muscles that control:

Eye and eyelid movement
Facial expression
Chewing
Talking
Swallowing
Arms and legs

The muscles that control breathing and neck movements also may be affected.

is mg the disease that relates to the thymus gland? its interesting that there could be a link to mg-thymus-cidp??? I did a lot of research on the thymus before i went out to mayo trying to connect info that it may be the cause of my abnormal antibody. As it turned out the particular antibody that I am producing is not made by the thymus (according to Dr Dyck)—but that doesnt rule out others. Just an interesting concept i thought i would throw out there—i guess in some cases removing the thymus fixes the mg. Lori

Gabriel100,

While I can imagine that one could have both MG and CIDP with variatons in their dominance, I am surprised to read that they are difficult to distinguish. I thought MG was an autoimmune disease in which the acetocholine receptors in the muscles are under attack, preventing the nerve impulses from activating the muscle, while CIDP was an autoimmune disease in which there is both inflammation of the nerves and demyelination. I would think a NCV/EMG study would differentiate the two. In MG, I would expect the EMG results to show compromise, but the NCV would look normal. In CIDP, I would expect the reverse. What am I missing?

~MarkEns

Just checking- Apparently the forum won’t put url’s around a link if it’s in the title. hmmmmm.

Regarding diagnosis of MG (Myasthenia-Gravis) this Mayo clinic website states-

“[I]…Blood analysis. A blood test checks for the abnormal antibodies in myasthenia gravis that may be blocking your muscle receptors from nerve signals.

Edrophonium test. Your doctor injects a chemical (edrophonium) into your bloodstream. Sudden but temporary improvement of muscle strength can indicate myasthenia gravis….[/I]”

A person could consider CIDP & MG interlinked if you only consider this, for example,

“…Plasmapheresis and intravenous immune globulin therapy. If you have a severe case that includes arm or leg weakness, or difficulty talking, eating or breathing, your doctor may recommend plasmapheresis or intravenous immune globulin therapy….”

However, as pointed out above, it would appear any significant Diagnostic similarities end there.

For more on the testing, the NIH says this, including a description of how nerve testing is used to diagnose the condition-

“[I]…A special blood test can detect the presence of immune molecules or acetylcholine receptor antibodies. Most patients with myasthenia gravis have abnormally elevated levels of these antibodies. Recently, a second antibody—called the anti-MuSK antibody—has been found in about 30 to 40 percent of individuals with myasthenia gravis who do not have acetylcholine receptor antibodies. This antibody can also be tested for in the blood. However, neither of these antibodies is present in some individuals with myasthenia gravis, most often in those with ocular myasthenia gravis.

The edrophonium test uses intravenous administration of edrophonium chloride to very briefly relieve weakness in people with myasthenia gravis. The drug blocks the degradation (breakdown) of acetylcholine and temporarily increases the levels of acetylcholine at the neuromuscular junction.

[COLOR=”Green”]Other methods to confirm the diagnosis include a version of nerve conduction study which tests for specific muscle “fatigue” by repetitive nerve stimulation. This test records weakening muscle responses when the nerves are repetitively stimulated by small pulses of electricity. Repetitive stimulation of a nerve during a nerve conduction study may demonstrate gradual decreases of the muscle action potential due to impaired nerve-to-muscle transmission….[/COLOR][/I]”