First, I agree with the other posters who mention that good controlled diet and supplements may well be beneficial even if one's neuropathy is not diabetic in origin, as steps taken to increase circulation to the nerves and get more nutrition and oxygen to them, and more waste products away from them, are good in any case. Diabetic neuropathy is primarily ischemic (circulatory) in nature, but a lot of other caused of neuropathy (toxicity, vascular autoimmunities) also have ischemic components.
nodsirrah--yes, that skin biopsy result seems pretty indicative of small-fiber neuropathy. Have you taken a look at the information from the Washington University/St Louis neuromuscular site? It's written in medical shorthand, but it's a very comprehesive database:
Don't know about the people at Mt. Sinai--the major research/clinical facility in NYC for neuropathy is the Cornell-Weill Center for Peripheral Neuropathy, which is also affiliated with the Columbia Presbyterian system. Some of the most influential research into neuropathy has come from there (through Drs. Latov, Chin, Brannigan, et. al.)--probably second only to Johns Hopkins in papers published in the area.
Wide-O--be very careful of doctors who will immediately blame a neuropathic symptom set on alcohol consumption. It's not that alcohol consumption is large quantities can't result in neuropathy (both through direct alcohol toxicity and through the nutrient deficiency that often results from people who drink large quantities), but there are a lot of doctors who only have to hear the word "alcohol" to abandon the responsibility of taking a full history and doing appropriate testing. This happens to diabetics, too, by the way--yes, diabetes causes neuropathy, but it's not the source of the problem in all diabetics.