Looking into histamine and neuropathy:
http://cat.inist.fr/?aModele=afficheN&cpsidt=14156441

This MAY explain why, when I'm extremely itchy, the SFN in my hands and feet is worse?

Thoughts?
ADDITION:
Found this on CNN.com (http://www.cnn.com/HEALTH/diet.fitne.../msg.avoiding/)
"Sufferers of MSG's effects are not experiencing an "allergy." Instead, they are experiencing the results of direct nerve stimulation and possible nerve damage, although the latter has not been verified in humans. Emergency room physician George R. Schwartz, author of "In Bad Taste: The MSG Symptom Complex," says MSG is a "neurotoxin," a substance that actually induces nerve changes and possible nerve damage. "