EPILEPSY OF INFANCY WITH MIGRATING FOCAL SEIZURES (EIMFS)

OVERVIEW

This syndrome is rare and characterized by the onset of high frequency intractable multifocal seizures with developmental regression in the first year of life. Seizures arise independently in both hemispheres and can migrate from one cortical region to another. Ultimately, severe neurodevelopment impairment is present and life expectancy is reduced.

NOTE Epilepsy of infancy with migrating focal seizures is a syndrome with developmental and epileptic encephalopathy.

Clinical context

This syndrome typically has onset in the first six months of life (mean 3 months), but later onset in the first year of life has been reported. Both sexes are equally affected. Antecedent and birth history is typically normal. Head size and neurological examination are usually normal at onset. Most patients develop microcephaly by 1 year of age. Development may be normal at onset, but regression occurs. Movement disorder may be seen. Prognosis is poor with ongoing intractable seizures, severe neurological impairments and reduced life expectancy, although a milder evolution has been reported in a few children.