"Classic" Guillain Barre is an acute-onset autoimmune demyelinating ployneuropathy, but not everyone undergoes the same mechanism or the same symptoms. Some have patchier symptoms not requiring hospitalization' some do not experience demyelination, but an axonal attack, depending on just what molecular mimicry is going on from the atuoimmunity.

The leading theory behind my idiopathic acute-onset body-wide burning sensory neuropathy of April 2003, which has been slowly resolving over the years, is that it was such a variant, in which my activated immune system attacked my small, unmyelinated fibers--the ones that control the sensations of pain and temperature--due to these fibers having a molecular structure similar to a pathogen that my body mounted a response to. I neve had motor symptoms, but the small-fiber pain was very debilitating for weeks/months, until the Neurontin reached therapuetic levels in my system. Small fiber damage was confirmed by skin biopsy (after hundreds of other negative/normal tests, including spinal tap).

See:

http://neuromuscular.wustl.edu/antibody/gbs.htm

BTW, Chronic Inflammatory Demyelinating Polyneuropathy--CIDP for short--is thought to be the slower onset (sub-acute, such as Dahlek experienced) analog of Guillain Barre. Sometimes the two are difficult to distinguish.