Acute Motor Axonal Neuropathy (AMAN)

Acute motor axonal neuropathy (AMAN) is a pure motor axonal subtype of Guillain-Barré syndrome (GBS). In Asia and Central and South America, it is a major subtype of GBS. AMAN progresses more rapidly and has an earlier peak than demyelinating GBS; tendon reflexes are relatively preserved or even exaggerated, and autonomic dysfunction is rare. Molecular mimicry of human gangliosides by Campylobacter jejuni lipooligosaccharides is believed to be the main pathophysiological process. In addition to axonal degeneration, electrophysiology shows rapidly reversible nerve conduction blockade or slowing, presumably due to pathological changes at the nodes or paranodal segments. Therapy is on the lines of GBS with variable outcomes.