MYOCLONIC EPILEPSY IN INFANCY (MEI)

OVERVIEW

This epilepsy syndrome is rare. Myoclonic seizures are the only seizure type seen at epilepsy onset and are seen frequently. They may be activated by photic stimulation, sudden noise or touch. Seizures are self-limited, ceasing within 6 months to 5 years from onset. Generalized tonic-clonic seizures may be seen in later life.

NOTE Self-limited refers to seizures having a high likelihood of spontaneously remitting at a predictable age.

Clinical context

This syndrome is characterized by the onset of myoclonic seizures between the ages of 6-18 months (range 4 months to 3 years). Males are twice as likely to be affected as females. Antecedent and birth history is unremarkable. Head size and neurological examination are normal. Prior development is usually normal. Cognitive, motor and behavioral difficulties are reported, especially if seizures are poorly controlled. Developmental outcome is normal in 60-85% of cases. Mild intellectual impairment and attention problems can be seen.