--among people who suffer from sensory small fiber neuropathy, autonomic symptoms are probably more common that is realized, although often the symptoms are mild or "subclinical".

The most common autonomic symptoms that are reported are hypo or hyperhydrosis--disorders of sweating (and one of the most commonly used tests for autonomic small fiber involvement is the "sweat test"--sudomotor axon reflex testing), but there are a decent number who report some degree of orthostatic hypotension (blood pressure reduction on quick standing), and some even report problems with gastric emptying/motility/constipation.

Of course, gastric dysregulation is common in diabetes, in which the first nerves typically damaged are the small fiber ones; diabetic autonomic neuropathy is recognized as a specific clinical entity.

See:


http://neuromuscular.wustl.edu/autonomic.html

http://neuromuscular.wustl.edu/senso...tml#idiopathic

http://neuromuscular.wustl.edu/sensory-small.html