Hi LouLou
Sorry to hear you are having to deal with SFN but equally glad to hear you are getting what sounds like some good treatment from a responsive neuro.
Your post jogged my memory of an article I read recently specifically about a type of SFN being a a variant of GB.
Here's the link:
http://jnnp.bmj.com/content/72/4/540.full
"Acute small fibre sensory neuropathy: another variant of Guillain-Barré syndrome?"
Although the article is dated 2001 it has a lot of info that you may find useful.
All the best for your IVIG trial. Let us know how you get on.