Treatment responsive GABA(B)-receptor limbic encephalitis presenting as new onset super-refractory status epilepticus (NORSE) in a Deployed U.S. Soldier (P4.233)

A 23-year-old, previously healthy, deployed U.S. soldier presented with bilateral temporal lobe seizures recalcitrant to multiple antiepileptic drugs and anti-seizure anaesthetic agents. He received methylprednisolone, intravenous immunoglobulins, plasma exchange, and rituximab for presumed autoimmune encephalitis before achieving seizure freedom. Six weeks after presentation, the aetiology of his refractory seizures was found to be due to autoantibodies targeting the anti-GABA(B)-receptor. This case is noteworthy for being the first reported case of anti-GABA(B)-receptor limbic encephalitis presenting with new-onset refractory status epilepticus (NORSE), a clinical syndrome that often carries a grave prognosis and in which a treatable aetiology is often never discovered. Our case also supports testing for GABA-receptor autoantibodies and the upfront use of multi-modal immunotherapy in patients presenting with limbic encephalitis and new refractory seizures.