It sounds like you are concerned that the small fiber neuropathy may be autonomic. Make sure where you are going next, has an autonomic lab. There are not that many places that have autonomic labs, and that is what is needed. Tilt Table, QSARTS, Thermoregulatory Sweat Test, the Cardiac stuff R to R breathing, Valsalva etc. Oh and you probably need a GI consult for transit time to see if you have GI involvement.

Vanderbilt has an Autonomic Lab.

There are several up north here, I think most of them were mentioned already.

Also, how much has been done to discover the CAUSE of your neuropathy?