Efficacy of ketogenic diet in severe refractory status epilepticus initiating fever induced refractory epileptic encephalopathy in school age children (FIRES)

P>Purpose: Fever induced refractory epileptic encephalopathy in school age children (FIRES) is a devastating condition initiated by prolonged perisylvian refractory status epilepticus (SE) triggered by fever of unknown cause. SE may last more than 1 month, and this condition may evolve into pharmacoresistant epilepsy associated with severe cognitive impairment. We aimed to report the effect of ketogenic diet (KD) in this condition. Methods: Over the last 12 years we collected data of nine patients with FIRES who received a 4:1 ratio of fat to combined protein and carbohydrate KD. They presented with SE refractory to conventional antiepileptic treatment. Results: In seven patients, KD was efficacious within 2-4 days (mean 2 days) following the onset of ketonuria and 4-6 days (mean 4.8 days) following the onset of the diet. In one responder, early disruption of the diet was followed by relapse of intractable SE, and the patient died. Epilepsy affected the other six responders within a few months. Discussion: KD may be an alternative therapy for refractory SE in FIRES and might be proposed in other types of refractory SE in childhood.