--but that is not a very helpful criterion in these cases, as we don't know what your nerve fiber densities were you had symptoms--in other words, there is no 'normal, healthy baseline' to compare these to.

This is one of the big problems with the rather arbitrary cut-off of below 5th percentile and above 95th percentile for diagnosis of small-fiber neuropathy (I've written about this a number of times here); it's also why they are supposed to report the condition of the fibers they see under electron microscopy.

And, yes, the normed standards that originally came from Johns Hopkins were for the most part determined from people older than you, so that is another interpretive problem. It is know that normal nerve fiber density does decrease with age in general, but there is great individual variation.

It is interesting, though that the sweat gland nerve fiber density was apparently of lower percentile (if I'm reading this correctly). Small, unmyelinated fibers in the skin subsume the sensations of pain and temperature, but they also control the expression of many autonomic functions, such as sweating and blood pressure. These results would be consistent with some degree of small-fiber autonomic neuropathy.

Take a look at:

https://www.therapath.com/ENFD.php