Childhood absence epilepsy and juvenile absence epilepsy
Childhood absence epilepsy represents about 12% of childhood epilepsy.101 Onset is at school age. A genetic background is often observed (see section on genetic and molecular basis). Very frequent, typical absence seizures (up to hundreds per day) are observed, lasting about 10 s, accompanied by rhythmic 3 Hz generalised spike and wave complexes. Absences disappear before adulthood in up to 90% of cases in which no other seizure types are associated. If absences persist, general tonic-clonic seizures usually appear. Early and late onset (<4 and >9 years), initial drug resistance, and photosensitivity have a less favourable prognosis.
Juvenile absence epilepsy starts at around 10–12 years and is partly overlaps with juvenile myoclonic epilepsy. Absence seizures cluster upon awakening. General tonic-clonic seizures, often precipitated by sleep deprivation, occur in up to 80% and photosensitivity in 20%. Long-term prognosis is unclear.
If you have a child who you think may have this condition and you would like us to review the diagnosis or provide genetic testing please contact us at neuroscience@meyer.it.