Doctors have been known to misread and not understand B12 levels.
Do you know your numbers?

MP at age 15 is unusual. It could imply an injury, or wearing very tight clothing/jeans. If you have not had abdominal surgery or an injury that is very unusual.

Nutritional damage is also possible, but there would be other nerves affected I would think early on. Neck cervical damage is also a potential culprit.
Have you had tests on your spine?

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

I have had a very hard time using my writing hand J.for the last 2 years
with writing hand. I started to finally do what you did write my name
and copy on so hand didn't look shaky..Bob the same thing,we got
pneumonia shots,at same time,he is having trouble with balance. Do
you remember having a fever when you got innoculation? Hugs Sue
I have been told don't care how you do make a x,that so badly hurts.
Pain wise my can't let my fingers touch ,to much pain.

Hi there - and forgive me if I shouldn't reply to you all at once - still working my way around your excellent board!

First of all thank you all so much replying - I thought some expert patients would be the best people to approach... and you are!

Hi Melody L - I haven't had a spinal tap.. but think I shall ask for one. I thought they would give me one to finally dismiss MS but they didn't want to!

I do have pain - not all the time and different in different places e.g. stabbing pains in the ends of my left hand fingers (the problem hand) and in the left big toe (really quite painful)... but actually haven't had these for a while. I also have a tight band kind of pain just below my left knee. The pain in my thighs is a stabbing pain just above the knee (at the edge of the numb patches). I also have had buzzing in toes and thighs. Pain in my thighs was actually much worse about 15-18 years ago when my right thigh got dramatically worse over the course of night and then over the next year: stabbing, buzzing, burning, some spasms (restless leg?), bubbling sensations. It then settled down into a slower pattern. The pain in my left hand and arm is more of an ache (I feel like I want to hold it or put it in a sling). It also feels sensitive and painful if I squeeze it if you see what I mean.

MrsD - I will try and get my hands on my B12 results over the next few days. I note from reading one of the links that it can show as pale optics... and I just paid to get hold of all my medical records for my whole life... and at my second neuro at 18 (when the leg became markedly worse) she notes that one eye had a pale optic nerve... but felt no need to pursue that or tell me that she suspected MS! The later neuro who diagnosed MP also noted that it was very rare in someone so young. I don't remember wearing tight clothes much. I have had no surgery... although lots of falls from my horse as a teenager... My scoliosis is at the top though near my neck.

Dahlek - the links are absolutely fabulous... so clearly laid out that I can definitely get my head around them before I see the doc. I did actually have a bad case of pneuomonia at the age of 9/10... my first numb thigh patch slowed up a few years after that... well that is when I first noticed it but it could have started from that point but been very subtle I suppose (progression was very slow at the beginning). I have had lots of flu and penumonia jabs too as I developed asthma from the pneumonia... although after doing all my MS research I declined to have them last year and won't have them again I think.

You are spot on with the fear actually - after living in abject terror with all of this for so long... last summer something snapped and I thought that's it I'm sorting this out now... the fear level definitely went down and as long as I am moving forward and learning about all of these things I feel so much better.

Shiney Sue - I do hope things get better for you - it is so frustrating.

Again - thank you all for your input - I feel like a door has opened up in my brain if you see what I mean!

Best wishes to you all!