Which statement best describes AMSAN without using the acronym?

• A. The axonal variant that is less common and more severe than the other axonal Guillain-Barré subtypes
• B. Primarily motor with preserved sensation
• C. Involves autonomic fibers only
• D. Pure sensory axonal neuropathy

Answer: (A)

Acute motor and sensory axonal neuropathy is a Guillain-Barré syndrome variant in which the disease damages the axons of both motor and sensory nerves. It appears less frequently than the other axonal form and tends to have a more severe clinical course, with more pronounced weakness, sensory loss, and slower recovery. Clinically you see rapid, symmetric weakness with sensory symptoms, and autonomic disturbances can accompany. Nerve conduction studies show reduced or absent amplitudes of motor and sensory responses with relatively preserved conduction velocity, reflecting axonal damage rather than demyelination. This combination—axonal involvement of both motor and sensory fibers, its relative rarity, and its tendency toward a more severe course—makes the statement describing it as the less common and more severe axonal Guillain-Barré subtype the best description.