I think you should entertain another rheumy opinion (whether you go back to the first, or seek out another).

Your ANA is tell-tale of autoimmune...just need to figure out which one. I would also suspect your SFN is directly related to your AI disease. And the sooner you figure this out, the sooner you can consider treatment geared toward autoimmune (like IVIG, steroids, Rituxan, Plaquenil etc). Unfortunately, the longer you wait on treating autoimmune related neuropathy, the lower your chances of reversing damage.

My personal opinion on lip biopsy, is if there is ANY lymphocytic infiltrate, then there is obviously an autoimmune process going on. Lymphocytes are NOT supposed to be present. It may not be enough for positive Dx (YET), but it certainly is indicative of an abnormal process. Just a thought.

BTW, how long have you been dealing with this? It may be that your at early stages and that may be why your biopsy is not showing completely positive.

Any other symptoms: joint pain, fatigue, rashes, GI problems, etc??

What are you doing for mgmt at this point?