Pharmacoresistant epileptic eyelid twitching in a child with a mutation in SYNGAP1

Area of Science:

• Genetics
• Neurology
• Epileptology

Background:

• The SYNGAP1 gene is implicated in neurodevelopmental disorders, including epilepsy.
• Drug-resistant epilepsy, particularly with eyelid myoclonia, requires detailed case reporting for better understanding.

Observation:

• A 4-year-old boy presented with recurrent epileptic eyelid twitching starting at 1 year and 5 months.
• Seizures involved upward eye deviation, motion arrest, loss of consciousness, and eyelid twitching, occurring over 50 times daily.
• Moderate psychomotor developmental delay and unsteady gait were observed; neuroimaging was normal.

Findings:

• Ictal EEG revealed generalized rhythmic slow or spike-and-wave complex activity with posterior predominance.
• The patient's seizures were refractory to carbamazepine and levetiracetam but responded to ethosuximide and lamotrigine.
• Genetic analysis identified a c.3583-6 G>A mutation in the SYNGAP1 gene.

Implications:

• SYNGAP1 gene analysis is crucial for intellectually disabled patients with early-onset, drug-resistant eyelid twitching and photosensitivity.
• Further research into SYNGAP1 gene function is necessary for developing targeted epilepsy treatments.
• This case highlights the importance of integrating genetic testing into the diagnostic workup for specific epilepsy syndromes.