Mesial temporal sclerosis in a cohort of children with SCN1A gene mutation.

Mesial temporal sclerosis is uncommon in childhood but has been associated with febrile status epilepticus. SCN1A gene mutations are linked to multiple epilepsy syndromes with patients frequently presenting with prolonged febrile seizures. After observing mesial temporal sclerosis in a child with SCN1A gene mutation, we retrospectively reviewed magnetic resonance imaging (MRI) findings in all patients with SCN1A gene mutation identified between 2005 and 2010. We identified 20 patients with SCN1A mutations. Six patients had evidence of definite mesial temporal sclerosis with 2 patients having bilateral abnormalities. Another 4 patients were defined as having possible mesial temporal sclerosis. This patient group revealed that 50% had findings consistent with definite or possible mesial temporal sclerosis and many did not have a history of prolonged febrile seizures. We conclude that mesial temporal sclerosis is a common finding in children with SCN1A mutations. Many of these children will have Dravet syndrome but not all.