A 68-year-old develops subacute memory impairment, behavioural change and dozens of brief stereotyped unilateral facial and arm contractions each

Question

A 68-year-old develops subacute memory impairment, behavioural change and dozens of brief stereotyped unilateral facial and arm contractions each day. Serum sodium is 122 mmol/L; MRI is initially unremarkable and CSF infection studies are negative. Anti-LGI1 antibodies are pending. What is the most appropriate immediate management?

Accepted Answer

Start first-line immunotherapy for probable autoimmune encephalitis while continuing diagnostic evaluation

Answer

Begin long-term antipsychotic treatment because behavioural change is the primary clinical syndrome

Answer

Use symptomatic antiseizure treatment and review management after serum antibody results return

Answer

Treat the hyponatraemia and seizures symptomatically with interval MRI surveillance at six weeks

Answer

Perform diagnostic brain biopsy as the next investigation and reserve immunotherapy for histological confirmation

Chronic Lithium Cerebellar Toxicity — SCE Neurology MCQ