Autoimmune Encephalitis

Diagnosis

Autoimmune encephalitis (AE) is a condition where the immune system mistakenly attacks the brain, causing inflammation and neurological symptoms. Early and accurate diagnosis is crucial, as AE can be misdiagnosed as other neurological or psychiatric conditions.

• Evaluation: A healthcare professional reviews your symptoms, medical history, and conducts a physical and neurological exam.

• Diagnostic Criteria: Specialists use AE criteria, looking for patterns of symptoms and testing for antibodies attacking brain receptors.

• Differential Diagnosis: Testing also helps rule out infections, cancer, and other autoimmune conditions.

Lab Tests

• Antibody Testing: Detects antibodies in the blood or cerebrospinal fluid (CSF).

• Lumbar Puncture: A procedure to collect CSF for testing. The lower back is numbed, and a hollow needle removes fluid for analysis.

Brain Imaging

• MRI: Detects signs of inflammation in the brain and helps rule out other causes.

• Other Imaging: May be done to check for tumors that could trigger AE.

Electroencephalogram (EEG)

• EEG measures the electrical activity of the brain.

• Helps detect seizure activity and supports diagnosis while ruling out other conditions.

Treatment

Treatment focuses on suppressing the immune system and addressing any underlying triggers, such as tumors.

Medicines

Immunotherapy is the main treatment to reduce immune system activity and inflammation:

• Intravenous (IV) Treatments:

  • Methylprednisolone (Solu-Medrol): High-dose steroids for 3–7 days.

  • Immunoglobulin (IVIg): Administered for 2–5 days.

• Oral Corticosteroids: Start with higher doses and taper slowly over weeks to months.

• Plasma Exchange: Removes harmful antibodies from the blood while returning blood cells to the body.

• Additional Immunotherapy: If symptoms persist, medicines like rituximab, cyclophosphamide, or tocilizumab may be recommended.

Early treatment improves recovery and reduces the risk of permanent neurological damage or relapse.

Therapies and Rehabilitation

• Supportive care may include:

  • Treatment for epilepsy, sleep disorders, or movement difficulties.

  • Rehabilitation for memory, thinking, and speech difficulties.

  • Involvement of occupational, speech, and mental health professionals.

• Cancer-related AE: Treating the underlying cancer is essential and ongoing monitoring is needed.

Long-Term Outlook

• Recovery can take months to years.

• Many people experience improvement over 18–24 months, although some may have persistent mild or serious symptoms.

• Certain types of AE, like anti-NMDA receptor encephalitis and anti-LGI1 encephalitis, may relapse even years after recovery.

• Early diagnosis and treatment significantly improve long-term outcomes.