Antibody-mediated autoimmune encephalitis: A practical approach

Antibody-mediated autoimmune encephalitis (AE) is a heterogeneous group of inflammatory central nervous system disorders. Symptoms typically include subacute, progressive neuropsychiatric symptoms with associated cognitive dysfunction, movement disorders, and autoimmune seizures. The diagnosis should be based on objective neurologic dysfunction in combination with autoantibody testing. Treatment with immunotherapies requires both short-term and long-term strategies depending on the specific syndrome and potential for relapse. In this paper, we review key features of AE, focusing on syndromes involving cell surface and synaptic proteins, and share a practical approach to the diagnosis and management, including common pitfalls associated with nonspecific antibody findings. KEY POINTS AE is an umbrella term for a group of inflammatory central nervous system disorders associated with neuronal autoantibodies or other biomarkers of central nervous system autoimmunity. Common clinical presentations include progressive neurocognitive symptoms with concomitant movement disorders, seizures, and autonomic dysfunction that worsens over weeks to months. Objective clinical findings are needed to make the diagnosis of AE, including changes on magnetic resonance imaging,