1. A disease process involving a number of peripheral nerves (literal sense).
2. A nontraumatic generalized disorder of peripheral nerves, affecting the distal fibers most severely, with proximal shading (the feet are affected sooner or more severely than the hands), and typically symmetrically; most often affects motor and sensory fibers almost equally, but can involve either one, either solely or very disproportionately; classified as axon degenerating (axonal), or demyelinating; many causes, particularly metabolic and toxic; familial or sporadic.
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