--that this is a post-infectious neuropathy, either through direct infiltration of nerve by the pathogen or by autoimmune molecular mimicry (in the latter, your body mounts an immune response to the pathogen and may even fight it off, but if the pathogen has a shape that is similar molecularly to that of certain body tissues--in your case, peripheral nerve--the now activated immune system goes after anything with a similar molecular "shape" and produced symptoms).
I am one who it is suspected had an acute-onset body-wide molecular mimicry episode, although it has never been proven (and such assaults are VERY difficult to prove even with extensive testing, as they may involve antibodies unique to the individual). My small-fiber syndrome was finally confirmed by skin biopsy (all other test results, including nerve conduction studies and EMG, were negative or normal). My body-wide burning symptoms, though, certainly indicated something was goind on (but the doctors were clueless until I got to a specialty research/clinical center--the Cornell-Weill Center for Peripheral Neuropathy; that was where much of the testing and skin biopsy were done).
Yes, in these acute onset body wide situations, doctors are trained to look at central nervous system possibilities first (part of why MRI's are a good idea), and many are not aware of these Guillain-Barre type syndromes that do not necessarily involve demyelination of larger nerves but attack on the smaller, unmyelinated ones.
Acute onset neuropathies are typically infectious, toxic, or auotimmune:
I'd also recommend a visit to our neuropathy forum here--lots of expertise: