Which statement about AMAN is correct?

• A. It predominantly involves sensory deficits
• B. It is characterized by rapid progression and pure motor weakness without sensory loss
• C. It is the mildest form of Guillain-Barré syndrome
• D. It always has a favorable prognosis within weeks

Answer: (B)

AMAN is an acute motor neuropathy that is a motor-axonal form of Guillain-Barré syndrome. The key feature is that motor nerves are affected while sensory nerves are largely spared, so patients develop rapid, significant weakness with little or no sensory loss. This combination—swift progression of weakness and absence of meaningful sensory symptoms—best describes AMAN. The axonal nature often means recovery can be slower and more unpredictable than in demyelinating forms, which is why it isn’t described as a mild illness or as always having a quick, favorable recovery. Sensory deficits aren’t the defining feature of AMAN, so statements emphasizing sensory involvement or universal quick improvement don’t fit as well.