AMSAN clinical features typically include which of the following?

• A. Severe weakness with profound sensory loss
• B. Mild weakness with intact sensation
• C. Pure motor weakness with normal sensation
• D. No weakness but paresthesias

Answer: (A)

AMSAN is an acute motor-sensory axonal neuropathy, an axonal Guillain-Barré syndrome variant. Because the immune attack targets both motor and sensory axons, patients develop rapid, often profound weakness along with significant sensory disturbances such as numbness and loss of proprioception. Reflexes are typically diminished or absent, and autonomic changes may occur. Nerve conduction studies usually show reduced amplitudes of both motor and sensory responses with relatively preserved conduction velocity, reflecting axonal damage rather than demyelination. This combination—marked weakness plus substantial sensory loss—best fits AMSAN, whereas patterns with only motor involvement or sensory symptoms without weakness, or those showing demyelinating features, do not match this presentation.