Hemiconvulsion-Hemiplegia-Epilepsy Syndrome in the Setting of COVID-19 Infection and Multisystem Inflammatory Syndrome in Children

ABSTRACT

Objective: To present a case of Hemiconvulsion-Hemplegia-Epilepsy (HHE) Syndrome in a child with COVID-19 infection and Multisystem Inflammatory Syndrome in Children (MIS-C). Background: HHE Syndrome is a rare pediatric epilepsy syndrome that presents with prolonged unilateral convulsive status epilepticus in the setting of fever, followed by hemiparesis, unilateral hemispheric swelling and atrophy, and the development of epilepsy. Though it was first described over six decades ago, the pathophysiology is still poorly understood with multiple factors contributing, including hyperthermia, inflammation, and cytotoxic edema from prolonged ictal activity. Prognosis is variable, from the resolution of hemiplegia and seizures to permanent hemiparesis and refractory epilepsy. Design/Methods: This is a case report based on a chart review. Results: The patient is a 2-year-old boy with a history of one prior complex febrile seizure who presented with greater than one hour of convulsive status epilepticus in the setting of fever. The patient had a generalized tonic-clonic seizure with more prominent convulsions on the right side. The patient required intubation and was initially given multiple anti-seizure loads though continued to have persistent electrographic and electroclinical seizures. EEG showed lefthemispheric high amplitude spike/polyspike and wave discharges. The patient required continuous midazolam infusion with eventual control of seizures on levetiracetam, phenobarbital, and clobazam. The examination was notable for persistent right-sided hemiparesis with gradual improvement. MRI brain without contrast revealed T2 signal abnormality and restricted diffusion diffusely throughout the left cerebral hemisphere. Infectious workup was significant for positive COVID-19 PCR and elevated inflammatory markers, consistent with MIS-C. Conclusions: Our patient had prolonged focal convulsive status epilepticus in the setting of acute febrile illness secondary to COVID-19 and MIS-C leading to hemiparesis and diffuse left cerebral hemisphere edema on MRI brain consistent with HHE syndrome. More research is needed to elucidate further HHE syndrome's pathophysiology and assess long-term outcomes in patients with HHE syndrome.