Brief Answer:
Mononeuritis multiplex has many possible causes.

Detailed Answer:
I read your question carefully and I understand your concern.

The x-ray studies speak of some mild degenerative changes of the spine which are a common finding with the passing of the years and in itself need only treatment with physical therapy and pain treatment.
On the other hand nerve conduction test speaks of Mononeuritis multiplex which means damage to several peripheral nerves in different areas. As you can see it only describes the damage but it doesn't say much about its cause. The causes could be many and more tests are needed to find the cause.

Some common causes are diabetes, autoimmune rheumatological and connective tissue diseases (lupus, rheumatoid arthritis, vasculitis etc), infections etc.

Some common tests with which it is to be started are: blood count, fasting blood glucose, erythrocite sedimentation rate and c-reactive protein level, autoimmune screening (ANA, ANCA), lyme disease antibody titer, HIV, hepatitis, amyloidosis etc.

According to the answers to these tests and other possible signs you might have indicating towards one of these causes it will be decided on the probable cause. From the current data a rheumatological disease would seem like the primary hypothesis.

Specific treatment can vary and will depend on the cause which must be treated.
As for the treatment you are receiving now, it is ok to relieve the symptoms and is not doing any harm. However I don't see the point of using both Carbamazepine and Lyrica since they have similar mechanisms, it's usually one or the other not both, it seems more logical increasing the dose of one of them interrupting the other, rather than taking both at a very low dose as you seem to be doing (I recommend to continue with Lyrica twice daily).

I would suggest you consult about the findings of nerve testing with a neurologist as these findings must also be compared with neurological exam and your symptoms. It is not a common diagnosis and if no signs on exam perhaps a reconsideration of the diagnosis might be considered.

I remain at your disposal for further questions.

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Brief Answer:
Read below.

Detailed Answer:
The answer to whether it is serious depends as I said by its cause, it's not threatening in itself just disabilitating, but the cause can be serious.

So I do believe that further tests for the cause are necessary if that is the established diagnosis. At least tests for autoimmune rheumatological diseases, diabetes and inflammation which are routine tests.
Vitamin B12 deficiency can cause neurological symptoms, but it is not usually related to mononeuritis multiplex type of changes on conduction studies. Anyway you should take vitamin b12 supplements as you are doing to correct it.

I suggest you discuss it with your doctor again. Perhaps he doesn't believe the nerve conduction testing results to be correct, a repeat nerve conduction study and electromyography study might be performed by another specialist to compare if in doubt.

As for the symptoms they include pain, tingling, numbness sensation, weakness in one or more areas of the body corresponding to the nerves involved. There might be also signs found on neurological physical examination like loss of sensation, loss of reflexes, motor weakness etc.

I hope to have been of help.

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Brief Answer:
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Detailed Answer:
Degenerative changes can cause the numbness in hands or legs that you describe, if those changes lead to compression of nerve roots or spinal cord.

If that is the case the MRI will show such compression.

So, such hand and legs symptoms can be caused both by degenerative spine changes and mononeuritis multiplex. They are both neurological conditions but involving different link of the neurological pathway chain, the first involves the spine or nerve roots as they exit the spine, while the second means a damage more peripherally.

It is either one or the other though, it is unlikely that you have two different neurological involvements at the same time, so if the MRI shows such nerve or spine compression that would mean that the report of nerve conduction studies are questionable.

It seems the spinal cause is what your doctor thinks, since he has asked for the MRI, perhaps that is because of your neck pain which is not typical for mononeuritis multiplex.

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Brief Answer:
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Detailed Answer:
Thank you for sharing your MRI report.

I am sorry about the frustration you are feeling. You must understand though that the exams are not necessarily wrong, the issue is whether those findings on MRI and cervical spine explain your symptoms.

Hydromyelia can cause numbness in the limbs. But if it is only in the thoracic (dorsal) cord that would not explain the numbness in the hands it would have to involve the cervical region.
I suggest you consult a neurosurgeon to evaluate both the degree and extention of hydromyelia and your neurological symptoms. If the hydromyelia location corresponds to the symptoms than that is the probable cause and whether to have surgery will depend upon your symptoms, at times waiting is preferred having control MRI after a period of time to see whether it's evolving.

If it doesn't explain your symptoms then mononeuritis multiplex is the cause and you should have the tests I recommended to look for the cause.

The treatment you are taking now is fine, it is the right treatment to alleviate the symptoms, my recommendations refer to searching for the origin in order to stop the progress.

I realize these issues are at times difficult to understand. I tried to explain it in simple terms, I hope I was understandable to you.

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Brief Answer:
You are welcome.

Detailed Answer:
You are welcome, I hope things work out for the best.

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