Abstract
Febrile infection–related epilepsy syndrome (FIRES) is a severe epileptic syndrome
that manifests with refractory seizures or status epilepticus in previously healthy
children after banal febrile illness. The neuroimaging findings in the acute phase
of FIRES are nonspecific or normal. We report the case of a 7-year-old boy with FIRES
who presented with a reversible lesion in the splenium of the corpus callosum on brain
magnetic resonance imaging (MRI). The patient developed clusters of clonic seizures
with a deviation of the eyes after a 3-day history of fever. A reversible splenial
lesion was observed on brain MRI and, therefore, the initial diagnosis was mild encephalitis/encephalopathy
with a reversible splenial lesion (MERS). However, the intractable complex partial
seizures necessitated a long-term midazolam infusion, indicating that FIRES was a
more likely diagnosis than MERS. All other findings of this patient met the diagnostic
criteria for FIRES. With this diagnosis, a high-dose phenobarbital was administrated,
and the seizures were successfully controlled. This case indicated that FIRES should
be considered even in patients with a reversible splenial lesion associated with encephalitis/encephalopathy.
Keywords
FIRES - MERS - reversible splenial lesion - high-dose phenobarbital
