Autoimmune Encephalitis

Autoimmune Encephalitis is a serious but treatable condition in which the body's immune system mistakenly attacks the brain, causing inflammation. This can lead to confusion, memory loss, seizures, personality changes, and even psychosis. AE can occur on its own or be triggered by infections, cancer (paraneoplastic), or unknown causes.

Sudden memory loss or confusion; Personality or behavior changes; Hallucinations or delusions; Anxiety or paranoia; Seizures; Movement disorders (twitches, jerks, abnormal posture); Trouble speaking or understanding language; Sleep disturbances; Decreased consciousness or coma (in severe cases).

Caused by antibodies that attack specific brain proteins, disrupting brain function. Common causes include antibodies (e.g., anti-NMDA receptor, anti-GAD65, anti-AMPAR, anti-LGI1), infections that trigger autoimmunity (post-viral), cancer (especially ovarian teratomas, lung cancer, or breast cancer) triggering an immune response, or idiopathic.

MRI brain scan; Lumbar puncture (spinal tap) to look for inflammation; EEG to check for abnormal brain activity; Blood and CSF antibody testing; Cancer screening (CT, PET scan, ultrasound depending on age and gender).

High-dose corticosteroids (to reduce inflammation); IVIG (intravenous immune globulin) or plasmapheresis (removes harmful antibodies); Immunosuppressive drugs (e.g., rituximab, cyclophosphamide); Treating underlying cancer (if present); Rehabilitation for speech, memory, and motor function recovery.

Many patients recover fully or significantly, especially with early diagnosis and treatment. Recovery may take months to years, and some may have lingering cognitive or emotional effects. Relapses can occur and need long-term monitoring.

Estimated at 5-10 cases per million people per year. Increasing recognition in both adults and children. Anti-NMDA receptor encephalitis is more common in young women, often associated with ovarian teratomas.