Autoimmune dementia and encephalopathy.

Area of Science:

• Neuroimmunology
• Neurology
• Autoimmune Diseases

Background:

• Autoimmune dementia and encephalopathies (ADE) present diverse cognitive deficits.
• These conditions can mimic neurodegenerative dementia and arise from paraneoplastic or idiopathic autoimmune processes.
• Diagnostic clues include personal/family history of autoimmunity, inflammatory cerebrospinal fluid, autoantibodies, and MRI findings.

Purpose of the Study:

• To review the diagnosis and management of autoimmune dementia and encephalopathies.
• To differentiate between pathogenic autoantibodies targeting cell surface versus intracellular antigens.
• To highlight the role of immunotherapy and cancer detection in managing ADE.

Main Methods:

• Review of clinical presentations, diagnostic markers, and treatment strategies for ADE.
• Classification of autoantibodies based on antigen targets (cell surface vs. intracellular).
• Evaluation of treatment responses to immunotherapies, including corticosteroids and antibody-depleting agents.

Main Results:

• Cell surface autoantibodies (e.g., NMDAR) are often pathogenic and respond well to antibody-depleting therapies.
• Intracellular autoantibodies (e.g., anti-Hu) indicate T-cell mediated processes with variable treatment responses.
• Early immunotherapy, often starting with corticosteroids, and cancer treatment (if applicable) are crucial.

Conclusions:

• ADE diagnosis relies on a combination of clinical, serologic, and imaging findings.
• Treatment strategies should be tailored based on autoantibody type and underlying cause.
• Prognosis is variable, with paraneoplastic ADE and intracellular autoantibodies associated with poorer outcomes.