Pathologically distinct presentations of GBS
What are the two main pathologically distinct presentations of Guillain Barre syndrome?
1. Acute inflammatory demyelinating polyradiculoneuropathy (AIDP) due to an immune attack on Schwann cell membrane or myelin sheath sometimes with secondary axonal damage.
2. Acute (motor or motor-sensory) axonal neuropathy (AMAN or AMSAN) due to an immune attack against the axolemma/axoplasm. AMAN is much more common in Asia and occurs mainly in children. AMSAN may occur anywhere and affects adults preferentially. AMSAN has a much worse prognosis than AMAN, with only 20% of patients with the former ambulating at 1 year.