Somatosensory reflex seizures in a child with epilepsy related to novel SCN1A mutation

Mutations in SCN1A have been reported in patients with different types of epilepsy, including generalized epilepsy with febrile seizures plus, severe myoclonic epilepsy in infancy, malignant migrating partial seizures in infancy, and other infantile epileptic encephalopathies.

We report a case of a 10-month-old girl presented with reflex epileptic seizures provoked by somatosensory stimuli with a novel de novo mutation of SCN1A gene. She was observed to have seizures with eye deviation, unresponsiveness provoked by somatosensory stimuli of the face. Video-electroencephalography (EEG) revealed generalized spike-and-wave patterns. She experienced one or two focal clonic seizures per month over the 6 months while taking valproate and carbamazepine. At 22 months old, she was hospitalized with an episode of generalized tonic clonic febrile status epilepticus lasting for 45 min. Interictal sleep video-EEG showed sharp-and-slow wave discharges in the left occipital lobe with normal background activity. We found a de novo heterozygote mutation in SCN1A gene, c.1337A>C (p. Q422P).

To our knowledge, this mutation has not been previously described in the SCN1A gene and this is the first report of epilepsy related to SCN1A mutation as a presenting with reflex epilepsy of somatosensory stimuli. This case report contributes to an expanding clinical spectrum of patients with SCN1A mutations.