Treatment responsive GABA(B)‐receptor limbic encephalitis presenting as new‐onset super‐refractory status epilepticus (NORSE) in a deployed U.S. soldier

Abstract

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.

Clinical features and outcomes of Chinese patients with anti‑γ‑aminobutyric acid B receptor encephalitis

“…affects middle-aged and aged males who have a high risk of receptor encephalitis, usually manifesting as LE, and has symptoms including seizures, memory deficits, psychosis and altered consciousness (4)(5)(6)(7)(8)(9). Furthermore, seizures are frequently the initial and most prominent symptom, which are usually refractory to anti-epileptic drugs but exhibit a response to immunotherapy (4)(5)(6)(7)(8)(9)13). In the present study, all patients had seizures as the major symptom.…”

Paraneoplastic epilepsy

“…The lack of drug-drug interactions and limited myelosuppressive or hepatotoxic side effects are important considerations in patients who will be receiving chemotherapies and targeted therapies. Patients with SE are often difficult to treat and may require pharmacologically induced coma [42]. Early identification of paraneoplastic antibodies is essential in the management of this patient population as this leads to earlier treatment of the underlying malignancy [43].…”

Immunological GABAergic interactions and therapeutic applications in autoimmune diseases

“…It is increasingly recognized that autoantibodies against GAD and GABA receptors are a feature of some forms of autoimmune encephalitis and/or epilepsy [72,74,[86][87][88][89][90]. However, these patients often have autoantibodies to other neuronal target molecules, and the relative pathogenic role of each antibody is not always clear.…”