That is a very interesting article... especially for pointing out the complexity, of this disorder. I get the feeling, that many patients are not evaluated for CMT because of this.
I would like the Vit D elaborated. Do they mean D2? Which is what doctors typically use? Or D3 from sunlight and most OTC supplements?
There is this one paper on a kidney patient who happened to have CMT also, and a dialysis problem with calcium: It is the only paper that comes up with CMT and Vit D keywords on PubMed:
Sometimes when medical articles are made like this one, the authors search MedLine for other problems and will report even obscure papers, just for safety's sake.
I am reminded of a paper about GLA... (which is found in evening primrose oil), but is also the abbreviation for a toxin.
Papers searching for negative studies on GLA, (from evening primrose) found this toxin that shares the same abbreviation, and since then the link to GLA (from primrose) and seizures has been "cemented" and repeated infinitely on further websites and in papers.
Concerning Vit D... I found this interesting article about ALS and elevated calcium levels in the blood:
http://www.als-mda.org/publications/als/als3_4.html
So since we cannot find a definitive paper on Vit D and CMT at this time, having calcium serum levels drawn as well as Vit D levels might be a good idea. The only contraindication so far medically has been suggested for sarcoid patients.
At this time Vit D treatments in US are still substandard. And I personally suspect more PNers should be tested for CMT than they are now.
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