Hi Terrence

Welcome to NT. Hopefully someone will be along soon to give you an accurate answer to your question.

Maybe your neurologist has a specific reason for wanting a lumbar puncture (ask him why he wants it done and what he expects it to show before you consent to the procedure). It's not unusual for people here with PN to have had a skin biopsy (a punch biopsy) done to look for small fiber neuropathy. Sometimes this gives a positive result and confirms the diagnosis - but also a negative result can be found but the person still has some form of neropathy.

There are more than 100 different types of neuropathy with just as many causes. Trying to identify the cause can require a lot of 'detective' work. I'm guessing you've been tested for Diabetes (this is the most common cause). Has your neurologist also checked your Vitamin B12 levels. If you can get copies of any blood tests your number should be above 400 pg/ml. The range still used by many doctors of a lower level of 200pg/ml being normal, is out of date.

There is lots of information on here about various types of PN. Take time to browse the PN forum - being informed will help you manage the condition.
I'll put in a couple of links here to websites which I've found useful:

http://www.ninds.nih.gov/disorders/p...neuropathy.htm

http://www.clevelandclinicmeded.com/...hy/Default.htm

It sounds as though you have a neurologist who is being thorough and not dismissive of your condition - many here don't get such a good response. If they're empathetic and willing to work with you to manage your PN then you're in good hands. Doctors are often pushed for time with explaining things so it may be usedful to take notes and come here for help with the details.

All the best for progress. Let us know how you get on.