--you might want to discuss on our neuropathy board (if you haven't found that already):

http://neurotalk.psychcentral.com/forum20.html

There are numerous autoimmune diseases that can result in neuropathy, and not all of them are the anti-nuclear antibody types that rheumatologists usually treat. Some of them involve other autoantibodies, to peripheral nerve or to other tissues, and the neuropathy results from secondary compressive mechanisms.

See:

http://neuromuscular.wustl.edu/nother/autoantibody.html