Pathologic studies of acute motor axonal neuropathy show strong eviden
ce of the presence of primary axonal Guillain-Barre syndrome (GBS). Th
e pathogenesis of axonal GBS is speculated to be as follows: (1) Infec
tion by an organism induces the high production of a crossreactive ant
ibody between an infectious agent and the motor nerve axon in patients
with a particular immunogenetic background. (2) The antineural antibo
dy binds to the motor nerve terminals, thereby inhibiting motoneuron e
xcitability and causing muscular weakness. (3) Binding of the antineur
al antibody, or subsequent functional impairment of the motoneurons, c
auses the motor axon to degenerate from the terminals. (4) In severe c
ases, extensive axonal loss and central chromatolysis of the motoneuro
ns occur. These inhibit recovery and lead to a poor functional prognos
is. (C) 1994 John Wiley & Sons, Inc.