The Role of Monoclonal Antibodies in Contrasting Cases of Norse

ABSTRACT

1. A 42-year-old female developed status ten days following admission for alcohol-related liver disease. MRI brain showed symmetrical medial temporal high signal. No cause was identified. Though the convulsive seizures settled, focal seizures persisted. A second MRI showed extensive multi-lobar signal change, presumed inflammatory in nature. Pulsed methylprednisolone and plasma exchange were ineffective. Tocilizumab was administered ten weeks following onset of seizures. Sequential MRIs showed resolution of inflammatory changes. The patient was discharged to rehabilitation-Modified Rankin Score 3. 2. A 79-year-old female presented with convulsive NORSE, 24hours after first dose of Pfizer COVID vaccine. She had a background of vascular dementia. The patient never recovered her GCS. Convulsive seizures were replaced by epilepsy partialis continua. Sequential MRIs showed diffuse left parietal cortical high signal. An inflammatory aetiology was presumed, pulsed methylprednisolone and the ketogenic diet (3 months) were ineffective. Anakinra was administered on week twelve. Subsequent MRIs showed progression of confluent white matter disease, now bi-hemispheric. She remains symptomatic, a year post presentation. We hypothesise that both patients had NORSE arising from an unidentified inflammatory aetiology. Age and premorbid function are known to influence recovery. Early use of monoclonal antibodies may be beneficial, including in those with systemic disease.