In Guillain-Barré syndrome (GBS), the anti-GQ1b antibody is MOST associated with which clinical variant?

• A Classic AIDP (ascending flaccid paralysis)
• B AMAN (acute motor axonal neuropathy)
• C Pharyngeal-cervical-brachial variant
• D Miller Fisher syndrome (ophthalmoplegia, ataxia, areflexia) ✓

Explanation

Anti-GQ1b IgG antibodies are present in >90% of Miller Fisher syndrome (MFS) cases — the triad of ophthalmoplegia, ataxia, and areflexia without significant limb weakness. GQ1b ganglioside is concentrated in the oculomotor nerve at the paranodal region, explaining ocular involvement. AMAN is associated with anti-GM1 and anti-GD1a antibodies (often post-Campylobacter). The pharyngeal-cervical-brachial variant has anti-GT1a antibodies. Classic AIDP typically lacks specific antibody associations. MFS is generally self-limiting and has an excellent prognosis.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.