Pediatric new-onset super-refractory status epilepticus (NOSRSE): a case-series

Abstract

Background: New-onset super-refractory status epilepticus (NOSRSE) leads to functional deficits and residual epilepsy. This study aimed to describe pediatric NOSRSE cohort to gain clinical insights of their features.

Methods: A retrospective review of children with NOSRSE in 2013-2024 was conducted at two tertiary hospitals. Patient clinical data, including MRI, CSF profile, EEG, and treatments, were collected and reviewed. The primary outcome measure was the modified Rankin scale score (mRS) at 3-month post-seizure.

Results: Twenty-three patients with NOSRSE, with a median age of 7.9 years, were included. Twenty-one (91 %) had febrile infection-related epilepsy syndrome (FIRES). The initial cerebrospinal fluid (CSF) profile was normal in five (23 %), pleocytosis was present in nine (39 %), and CSF protein was elevated in 15 (68 %) patients. Initial Brain MRI was normal in 14 (61 %) patients. First- and second-line immunotherapy was delivered to 21 (91 %) and 15 (68 %) patients, respectively. The etiology was viral infection in two (9 %) patients, and presumed cryptogenic in the remaining. The primary outcome was poor (mRS ≥4) in 14 (61 %) patients and all had residual epilepsy. Elevated initial CSF protein levels were associated with poor outcomes. Mental status before treatment, time to immunotherapy, intubation of >2 weeks or tracheostomy, and the duration of anesthetics were also associated with the primary outcome.

Conclusion: Most pediatric NOSRSE patients presented as cryptogenic FIRES, with poor long-term outcomes. None of the patients with NOSRSE tested positive for autoimmune antibodies. Many showed permanent MRI changes but did not correlate with outcome. The initial CSF profile may serve as an objective disease severity marker in NOSRSE.

Keywords: Febrile infection-related epilepsy syndrome; New-onset refractory status epilepticus; Super-refractory status epilepticus.