Axonal Guillain-Barré syndrome: concepts and controversies

Area of Science:

• Neurology
• Immunology
• Infectious Diseases

Background:

• Acute motor axonal neuropathy (AMAN) is a significant subtype of Guillain-Barré syndrome (GBS), particularly prevalent in Asia and Central/South America, affecting 30-65% of GBS patients.
• AMAN is characterized by rapid progression, preserved tendon reflexes, and rare autonomic dysfunction, distinguishing it from demyelinating GBS forms.

Purpose of the Study:

• To elucidate the pathogenic mechanisms underlying Acute Motor Axonal Neuropathy (AMAN).
• To explore the role of molecular mimicry and autoimmune responses in AMAN pathophysiology.
• To identify potential targets for novel therapeutic interventions in AMAN.

Main Methods:

• Review of clinical and electrophysiological findings in AMAN patients.
• Analysis of the role of Campylobacter jejuni lipo-oligosaccharides in molecular mimicry.
• Investigation of autoantibody binding to gangliosides (GM1, GD1a) at the nodes of Ranvier.

Main Results:

• AMAN is primarily caused by molecular mimicry involving Campylobacter jejuni and human gangliosides.
• Electrophysiology reveals rapidly reversible nerve conduction block or slowing, indicative of nodal/paranodal pathology.
• Autoantibodies against GM1/GD1a gangliosides activate complement, disrupting axoglial junctions and leading to nerve conduction failure.

Conclusions:

• Understanding AMAN's mechanism, including ganglioside autoantibody involvement, is crucial for developing targeted treatments.
• The pathophysiology involves complement-mediated damage at the nodes of Ranvier, affecting sodium-channel clusters and axoglial junctions.
• Further research into AMAN pathogenesis may improve patient outcomes and treatment strategies.