[P1-129] Anti-GQ1b antibody syndrome with acute ophthalmoplegia in Chinese paediatric patients
Immunoglobin G antibody against GQ1b is commonly associated with Miller-Fisher syndrome (MFS) which is characterised by a clinical triad of ataxia, areflexia and ophthalmoplegia. However, its presence has also been identified in other closely-related clinical syndromes such as Guillain-Barré syndrome (GBS) with ophthalmoplegia, Bickerstaff brainstem encephalitis (BBE) and acute ophthalmoplegia without ataxia.
We retrospectively reported four Chinese paediatric patients (5–14 years old) from Hong Kong in a regional hospital with positive anti-GQ1b antibody. These cases were classified as MFS (n=2), BBE (n=1) and acute ophthalmoplegia without ataxia (n=1) according to their clinical manifestations. All cases presented with acute external ophthalmoplegia (limited upward and horizontal gaze=2; limited downward and horizontal gaze=1; and limited gaze in all directions=1), clinical diplopia and ptosis. These patients also had internal ophthalmoplegia, namely mydriasis (n=2) and slugglish pupillary light responses (n=2). Other common non-ophthalmic manifestations in our cases include areflexia / hyporeflexia (100%), ataxia (75%), muscle weakness (50%) and facial nerve involvement (50%).
GQ1b ganglioside is highly expressed in the paranodes and neurotransmitter junction of the oculomotor, trochlear and abducens nerves and the ciliary ganglia. Patients with positive anti-GQ1b antibody are frequently presented with acute ophthalmoplegia with or without ptosis, plus variable symptoms of central and peripheral nervous systems.
Anti-GQ1b antibody syndrome has to be considered in patients with acute external ophthalmoplegia and for patients without weakness or ataxia in particular, the presence of internal ophthalmoplegia and / or areflexia / hyporeflexia may be the important clues to the underlying cause for external ophthalmoplegia.
We retrospectively reported four Chinese paediatric patients (5–14 years old) from Hong Kong in a regional hospital with positive anti-GQ1b antibody. These cases were classified as MFS (n=2), BBE (n=1) and acute ophthalmoplegia without ataxia (n=1) according to their clinical manifestations. All cases presented with acute external ophthalmoplegia (limited upward and horizontal gaze=2; limited downward and horizontal gaze=1; and limited gaze in all directions=1), clinical diplopia and ptosis. These patients also had internal ophthalmoplegia, namely mydriasis (n=2) and slugglish pupillary light responses (n=2). Other common non-ophthalmic manifestations in our cases include areflexia / hyporeflexia (100%), ataxia (75%), muscle weakness (50%) and facial nerve involvement (50%).
GQ1b ganglioside is highly expressed in the paranodes and neurotransmitter junction of the oculomotor, trochlear and abducens nerves and the ciliary ganglia. Patients with positive anti-GQ1b antibody are frequently presented with acute ophthalmoplegia with or without ptosis, plus variable symptoms of central and peripheral nervous systems.
Anti-GQ1b antibody syndrome has to be considered in patients with acute external ophthalmoplegia and for patients without weakness or ataxia in particular, the presence of internal ophthalmoplegia and / or areflexia / hyporeflexia may be the important clues to the underlying cause for external ophthalmoplegia.