I suffer from severe neuropathy through my feet and legs and to a lesser extent through my fingers and hands.
There can be several causes of this, they can be.
1. Injury - severe injury to your head, spinal cord etc.
2. Medications- some medications can cause this. Stopping the medication (talk to your Dr. first) can alleviate symptoms in some cases.
3. Heavy metals- Mercury and Lead can cause this. get a full blood workup-
4. Disease - certain diseases can cause Neuropathy.
5. Diet - a poor diet can flare neuropathy up. Find out about natural, organic foods.
Good luck and feel free to ask me, I am 39 and dealing with this for 5 years now.