No, not that simple as there are many that are genetic

As mentioned, there are a lot of different forms of CMT, but that is a general term you can use for hereditary neuropathies. Another term, less used I think, is HMSN, "hereditary motor and sensory neuropathy". As also mentioned, there's all sorts of different sub-types, and there is some overlap between the two different systems. (Kind of like the Dewey Decimal system and the Library of Congress system for organizing books.) Here's a brief article,
emedicine.medscape.com/article/1173104-overview

In my case, my doctor put in a pre-authorization for a genetic test and it was rejected by my health insurance. But the test is from Athena Diagnostics, who has a program by which they guarantee that the patient's out of pocket expense is limited to 20% of the cost (if you agree to the program and send your payment within 30 days of the test). So, the next time I saw him, he just sent in for the test. I had my blood drawn, received paperwork from Athena about the program, and paid them my 20%. I've received the results (MFN2: negative). I have no idea yet what my insurance company is going to say, but it's not my problem -- a piece of the paperwork allows Athena to argue with the insurance company on my behalf, to convince them to pay.

My insurance company rejected it because the result wouldn't make a difference in my care or in the outcome of the disease -- and I agree that it wouldn't, but it would give me some peace of mind and some understanding of what's causing my symptoms. It's still expensive, tho -- the test cost was $940 and so my 20% was $188.

Athena is the leading provider of genetic tests for CMT and hereditary neuropathies. They have vast panels that will test for everything they can, but my physician has been pretty focused on specific tests relate to my symptoms. You might ask your doc if there are some specific tests from Athena that would be appropriate (so that your 20% doesn't go through the roof).

Here's the scoop on the "Access Athena" program,
athenadiagnostics.com/content/ordering/access-athena

And their main web site is here (you can browse the tests they've got),
athenadiagnostics.com/

(You'll have to copy and paste the links since neurotalk doesn't trust me to post links yet.)

CMT is also known as Hereditary Motor Sensory Neuropathy (HMSN). HMSN is an alternative name for CMT as is Peroneal Muscle Atrophy which was used years back when they didn't know the different types. They only then knew it as CMT and/or Peroneal Muscle Atrophy. CMT is properly used to describe a neuropathy that affects sensory and motor axons. It is not a general term you can use for all hereditary neuropathies.

A few years back, they thought that the term HMSN would sound better than Charcot-Marie-Tooth as some people think it is a tooth problem. However, I find that the term HMSN is not much better as most lay people do not understand it anyway. It is a very complicated syndrome. There should be a better term than either of those in my view. There is much research going on for CMT also known as HMSN.

Your results of MFN2 is CMT2A2. Did the negative mean that you do not have that type? The type 2's are autosomal dominant axonal/neuronal. You probably know this.



http://www.athenadiagnostics.com does do the DNA blood testing for CMT also known as HMSN. There are 22 + types that they now can test for. There are 50 types they have identified so far and no end in sight. And yes, if they have to do the whole panel of tests for CMT that they now can test for, it is expensive. And yes, they do have a program to help with the cost. And your insurance "may" help with the cost.

An informative site: http://neuromuscular.wustl.edu/time/hmsn.html

Have they tested you for HNPP (Hereditary Neuropathy with liability to Pressure Palsies)? It is the opposite of CMT1A which is a duplication and HNPP is a deletion. http://www.hnpp.org I read in your other posts that a part of you (hand) will be numb but then it comes back to normal. This makes me wonder. Something to think about anyway. It's a good site.

Thanks for the info, Kitt, and for your interest. Yes, my negative result for the MFN2 test means that I don't have CMT2A2. A skin biopsy, and nerve conduction testing, indicates that my neuropathy is axonal.

Fascinating info on HNPP. There are some similarities between the symptoms listed and my experience. However, HNPP is "primarily demylenating" and my nerve loss is axonal. I also don't experience any muscle involvement to speak of (though that's variable in HNPP). Still, the info has spawned a new thread of research for me and I'll bring it up with my neurologist the next time I see him.

But I don't really want to hijack this thread... On my 'to do' list is getting all my symptoms and test results together and starting a thread for a review by all the fine folks who hang out here. Right now, my diagnosis is "ideopathic axonal peripheral neuropathy" and I'd like to make the "ideopathic" part go away. Well, I'd like to make all of it go away... Thanks again, Kitt.

One has to be careful with terminology here.

I think the word hereditary can be misleading.

1) there are genetic (hereditary) failures in nerve functions...CMT etc represent those.

2) People do inherit the tendency to have autoimmune problems.
So while this may be called hereditary, instead it is called autoimmune (inflammatory). Autoimmune PN can be treated with IVIG, plasmapharesis, or drugs that suppress the immune over-reactivity.

But the folks with genetic PN...do not have a treatment yet.

So I would urge Grisabella to get clarification from her doctor.
Anti-inflammatory drugs would not be helping genetic CMT IMO.
Continuing to use "hereditary" for PN here may confuse those with real genetic PN.

The term CMT is properly used to describe a neuropathy that affects sensory and motor axons. Patients with the disease are otherwise well. The designation CMT should not be used for inherited diseases that strongly affect other organs, such as the brain; these are syndromes in which neuropathy is typically an unimportant element (there are at least 100 such syndromes). (CMTA Report).

Again, CMT or the newer name HMSN, is properly used to describe a neuropathy that affects sensory and motor axons. It is most often inherited. CMT is the most common "inherited" neuropathy. It is genetic. There is no treatment/cure yet. Hopefully in the future.

I agree with the explanation of autoimmune.

There are many doctors even neurologists who do not know CMT. They read a few lines in a text book. And why would they know CMT as they probably have never seen a person with it. Or if they have, maybe just one or two. A person definitely needs an expert in the field of CMT. And there are those DNA blood tests which are a great help in determining the types, etc.

Grisabella does seem to have some symptoms that perhaps sound like CMT but she definitely needs to have some DNA blood testing done along with some family history. She also mentioned that 20 years ago CMT was brought up. As I said before, athenadisagnostics does have a program to help with the cost. I don't know how old she is but if she is 65 or more the cost is covered by Medicare I believe.

Hopefully, this information will help some people and those who do have CMT.

Thank you to everyone who has been contributing to this thread and is being so helpful. I really appreciate it, even if I don't totally understand it all.

My mother has rheumatoid arthritis and doctors have told me that the descendants of people with RA tend to have very obscure illnesses like this one, although to have PN isn't that common. And my neurologist said it doesn't really matter so much because the treatment for all the neuropathies is mostly the same. I never knew my father till I was grown up and he died two years later, but I know he had lots of trouble with his legs and feet. He was an alcoholic, though, and had been in a logging accident in his teens that broke both his legs so I assumed that was what was wrong with them.