I am betting that rite now you are sort of beyond the freaking out stages and just at a high pitch of medium panic? Well lots of us have been there in our own diagnoses....for some it didn't take as long tho!

I suggest that you start out with reading the stickies at the top of the forum...but to make things faster, since you're seeing the doc like probably tomorrow? Here's the quick tutorial....
First this is an outline about PN and how it's ultimately diagnosed...
http://www.aafp.org/afp/980215ap/poncelet.html
Next is a set of charts about diagnosing PN -eliminating all other possible causes...a list of tests and when used with the above site, well, they dovetail nicely as to all the steps that should be ultimately taken....
http://www.lizajane.org/

Just click on the blue and a new window should open for you to read....
I do have to ask tho? Did you have a pneumonia or flu before anything started? Possibly some innoculations? Even 4-6 months before? Something stubborn and the like? I ask because I've an auto-immune neuropathy, and that's what did me in...what's peculiar about your situation is the 'spottiness' of it all. Nonetheless? All the tests in the LizaJane worksheets and the diagnosis tutorial should be explored with that 'If This, then...However-But' kind of look out for anything key that mite be helpful to YOU and the DOCS in your evaluations. It's a mind boggling and head-against-the-wall-banging experienct to try and connect dots if they are to be connected. Most often they aren't connected nor are reasons found for all this dastardly STUFF happening to us? It's kind of like detective work...only less satisfying in many ways.
As for losing your hand use? I DID! Truly DID after my own immune PN onset! IT took me a year before I could clearly write my name on a check? And I used to do it ahead of time, so's I knew my hand wouldn't be so shaky. Happens even now on occasion...four plus years into it. Only thing I found that helped was physical therapy [PT] and it's something docs especially neuro's don't think of UNLESS you ask them! Soooo don't be shy? And please let us know how it goes? Rite now I'm betting it's an approach of 1/2 fear and 1/2 GO GET 'EM! w/a lot of mush in between. I've got all three tee-shirts! Just know lots of good folks have done this and you are gonna have to deal with this doc as your instincts and NEEDS tell you to. You have to be assertive and clear in your problems...even tho you don't 'know' the language of doc-speak and be more assertive about HELP ME! You mite get that help! I Sure hope so!!!!!!!!!!!!!!
Do not be afraid to ask questions...not one is too silly! Sometimes those are the most common and humbling ones among us! 's - j