--more often referred to as CIDP (chronic inflammatory demyelinating polyneuropathy) is an autoimmune condition that is often analogized to a slower, less acute onset of Guillain Barre syndrome.

There is an autoimmune attack on the myelin sheathing of the larger sensory and motor nerves, which results in degraded nerve signalling and a host of symptoms. Typically in CIDP the motor symptoms are greater than the sensory ones, though there are variants in which sensory symptoms are paramount. People with CIDP often notice problems with walking or gross motor control initially, and it is easy to confuse the condition with other neuromuscular diseases.

Given that the mechanism is autoimmune, this is a neuropathy condition that can frequently be treated by immune-modulating therapies such as intravenous immunoglobulin (IVIg) or plasmaphoresis. The trick is getting a doctor who suspects the condition, will do the right testing, and who will go to bat for immune modulating therapy if indicated (such therapies are extremely costly and insurance companies are not usually very cooperative).

See:

http://neuromuscular.wustl.edu/antib...mdem.html#cidp

http://www.gbs-cidp.org/home/cidp/cidp/

http://emedicine.medscape.com/article/1172965-overview