Testing of autonomic fibers from skin biopsy is not new. It does provide a good indication if there is autonomic dysfunction. BUT, there are more precise autonomic testing that is done if the patient is experiencing autonomic symptoms. QSART, and thermoregulatory sweat test are more specific in some ways...and there are also many cardiac testing for autonomic dysfunction (tilt table, 24 hour BP, etc).

Although autonomic function also comes from small fiber nerves, there are autonomic ganglia along the spine. The autoimmune process can attack this ganglia, just like the dorsal root ganglia.

Do you have autonomic problems?