We report three patients with severe Guillain-Barre syndrome (GBS). On
clinical examination, no sensory deficit was elicited. Electromyograp
hy (EMG) and motor nerve conduction velocity (NCV) studies were indica
tive of an axonal lesion. In two patients, we found total peripheral c
onduction block without volitional EMG activity, Sensory NCV and corti
cal median nerve evoked potentials remained normal, Sural nerve biopsy
revealed unequivocal alterations of sensory nerve fibers, some in the
form of primary demyelination, Therefore, these cases must bei classi
fied as combined motor-sensory syndromes despite the clinical and elec
trophysiological findings. Although total denervation of the extremity
muscles occurred, causing tetraparalysis, this manifestation appears
to be attributable to the secondary axonal variant. In contrast to pos
itive reports in literature, immunomodulatory treatment proved ineffec
tive in all three cases.