New-onset refractory status epilepticus (NORSE)--The potential role for immunotherapy

Area of Science:

• Neurology
• Immunology
• Critical Care Medicine

Background:

• New-onset refractory status epilepticus (NORSE) presents as persistent seizures without a clear cause in individuals without prior epilepsy.
• Optimal management strategies for NORSE remain challenging, with the specific role of immunotherapy (IT) not yet fully elucidated.
• Identifying potential treatments is crucial given the severity and complexity of NORSE.

Purpose of the Study:

• To analyze outcomes in patients with NORSE treated with immunotherapy (IT).
• To compare outcomes between patients receiving IT and those not receiving IT.
• To generate hypotheses for future research on IT's efficacy in NORSE.

Main Methods:

• Retrospective analysis of 11 patients diagnosed with NORSE at a single institution.
• Literature review and pooled analysis of existing NORSE case series.
• Comparison of outcomes in patients who received IT versus those who did not.

Main Results:

• In the single-institution series, 8 of 11 patients received IT, with 6 achieving favorable outcomes compared to 0 of 3 untreated patients (p=0.026).
• Autoantibodies, including anti-GAD and anti-NMDAR, were identified in 7 of 11 patients.
• Pooled analysis of all case series showed a statistically significant benefit for IT, with favorable outcomes in 42% of IT-treated patients versus 20% of untreated patients (p=0.022).

Conclusions:

• Immunotherapy may improve outcomes for patients with New-onset refractory status epilepticus (NORSE).
• Consideration of NORSE in refractory status epilepticus with negative investigations is recommended to facilitate early immunotherapy.
• Further prospective, multicenter studies are required to establish the definitive efficacy of immunotherapy in NORSE (currently Class IV evidence).