Can idiopathic small fiber neuropathy go away if no cause is determined?

Rarely if ever: Small fibers are poorly myelinated so small-fiber neuropathies are axonal. When there is enough axonal dropout, the damage is almost always permanent. When symptoms improve, it's usually because the neuropathy is so advanced it's "burned out." In fact, spontaneous remission of axonal neuropathy is so atypical that if it happens you have to reconsider the diagnosis.