muscle twitching
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I am not a doctor, but I have symptoms similar to yours. I have had fasciculations (along with paresthesias) for six months. I don't know exactly what's causing mine or yours, but I don't think you should be worried about MS, especially if your MRIs have been normal. I have read multiple times, including posts from the docs on this board, that fasciculations are not a common symptom of MS. Here are some comments that might help reassure you:
"Lower motor neuron signs such as fasciculations do not result from MS."
Source: http://www.mscare.org/journal/a0109/page_01.cfm
"Muscle fasciculations are usually not a part of MS. MS is an upper motor neuron disease and this type of central nervous system problem does not give the symptoms of muscle fasciculations."
Source: http://www.medhelp.org/forums/neuro/messages/31162.html
"I think that there are several reasons not to think that [the poster has] MS. First is the negative MRI. Actually, most people to come to the neurologist with complaints that seem like MS, who actually end up with the diagnosis of MS have MRI changes in the brain. They also have abnormal visual evoked potentials. The symptoms of muscle fasciculations is also not common in MS, especially as a presenting sign."
Source: http://medhelp.org/forums/neuro/messages/31306a.html
Good luck!
-Everett
Have you had your B12 level checked? If so, what kind of test did you have done? Normal serum B12 tests that most local labs do can be misleading for B12 deficiency. Low serum levels will always be present in someone who is B12 deficient because of diet (such as malnourished children in impoverished regions or some strict vegans), but people with malapsorption problems (which is most non-vegans in the developed world) *may* have high levels in their serum which is going unused by their bodies. There can be things that you consume that can falsely inflate your serum B12, and there can be reasons why you're not absorbing it. Some tests that can help are homocysteine and MMA, as these will often be elevated in people with B12 deficiency. There is also a Spectracell test that measure the functional intracellular deficiency of B12 in your lymphocytes, which is probably the best way to determine if you have a B12 deficiency.
Have you been tested for heavy metal toxicity?
Have you been tested for thyroid and adrenal function?
I had bacterial spinal meningitis when I was a kid. My entire life I've had weird neurological-type symptoms, many unexplained. I have twitching all over, and have for years. It comes and goes, but usually resurfaces during times of intense stress or change. If you've had EMG's and they've come back normal, then you're probably ok, but that's for your doctor to decide. Although many doctors don't seem to think much of it, I think that having a disease that effects your spine in such a way as meningitis can cause all kinds of issues for people down the road. Good luck to you, and I hope everything turns out fine.