A 45-year-old woman presents with rapidly progressive ascending weakness over 10 days, bilateral facial palsy, absent deep tendon reflexes, and dysautonomia. CSF shows albumin-cytological dissociation (protein 180 mg/dL, 3 cells). Nerve conduction studies show prolonged distal latencies, reduced conduction velocities, conduction block, and prolonged F-wave latencies. Which variant of GBS is this most consistent with?
- A Acute motor axonal neuropathy (AMAN)
- B Miller Fisher syndrome (MFS)
- C Pharyngeal-cervical-brachial variant
- D Acute inflammatory demyelinating polyneuropathy (AIDP) ✓
Explanation
The NCS findings of prolonged distal latencies, reduced conduction velocities, conduction block, and prolonged F-waves, combined with CSF albumino-cytological dissociation, are hallmarks of AIDP (the most common GBS subtype in Western countries). AMAN shows reduced CMAP amplitudes with preserved conduction velocities (axonal pattern) and is associated with Campylobacter jejuni infection and anti-GM1/GD1a antibodies. Miller Fisher syndrome presents with the triad of ophthalmoplegia, ataxia, and areflexia (anti-GQ1b antibodies) without prominent limb weakness. Pharyngeal-cervical-brachial variant affects throat, neck, and arms preferentially.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
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Written and medically reviewed by the StethoPrep medical team.