Ketogenic Diet for a Young Adult Patient With Chronic-Phase Febrile Infection-Related Epilepsy Syndrome

Febrile infection-related epilepsy syndrome (FIRES) is a rare disease, whereby refractory status epilepticus (a severe epileptic syndrome) occurs in previously healthy individuals following a febrile illness. Here, we report a patient with FIRES who received ketogenic diet (KD) therapy initiated in the chronic phase. A 21-year-old man presented with status epilepticus, following fever and headache. In the acute phase, his seizures were refractory to conventional antiepileptic drugs and were suppressed only by intravenous anesthetics. In the chronic phase, he showed frequent seizures with concurrent severe cognitive decline. Twenty-seven months after onset, the patient was started on KD. Consequently, his seizure frequency rapidly reduced while his cognitive function slowly improved, albeit incompletely. Recently, KD has been shown to both reduce seizures and improve cognitive prognoses in children with FIRES. Although early KD may help in both seizure control and cognitive prognosis, it is likely that KD can be applied to adult patients with chronic FIRES.