As I understand it Neuropathic pain is just that, i.e . pain which is caused by a nerve disorder. It is a symptom rather than a (specific) cause. In any particular case, the cause may be difficult to determine.

PN is when the disorder is of the "peripheral" nervous system, meaning generally nerves in the extremities - legs, arms etc - as opposed to the "central" nervous system - spinal cord etc

I realise that this probably does little to help in your case but it is useful to be clear about the terms.

For more information including a long list of the cause of Neuropathic pain, see http://www.patient.co.uk/showdoc/40025146/