What autoimmune encephalitis is
Autoimmune encephalitis occurs when antibodies attack neuronal surface proteins, synaptic proteins, or intracellular antigens, causing brain inflammation. This produces a wide range of symptoms including seizures, cognitive decline, psychiatric symptoms, movement disorders, and autonomic dysfunction. Unlike infectious encephalitis caused by viruses or bacteria, autoimmune encephalitis is driven by immune dysregulation.
Specific antibody types correlate with clinical syndromes. Anti-NMDA receptor encephalitis often affects young adults and presents with psychiatric symptoms, seizures, movement disorders, and autonomic instability. Anti-LGI1 encephalitis presents with faciobrachial dystonic seizures (brief arm jerks) and cognitive decline. Anti-CASPR2 encephalitis causes Morvan syndrome (neuromyotonia, autonomic dysfunction, insomnia). Paraneoplastic encephalitis occurs in association with cancer (especially small cell lung cancer, ovarian teratoma, breast cancer).
- Antibodies attack neuronal surface or synaptic proteins
- Symptoms: seizures, cognitive decline, psychiatric, movement disorders
- Anti-NMDA, anti-LGI1, anti-CASPR2 are common antibody types
- Paraneoplastic forms associated with underlying cancer
Related: Neurologist Kathmandu → · Dr. Jitendra Knowledge Hub → · ICHD-3 Topic →
Evaluation and immunotherapy
Evaluation includes MRI brain (may show T2/FLAIR hyperintensities, sometimes normal), EEG (to characterise seizures and background slowing), cerebrospinal fluid analysis (lymphocytic pleocytosis, elevated protein, oligoclonal bands), and antibody testing in serum and CSF. Cancer screening (CT chest, abdomen/pelvis, pelvic ultrasound, testicular ultrasound) is essential when paraneoplastic encephalitis is suspected.
Treatment involves immunotherapy to suppress the abnormal immune response. First-line immunotherapy includes corticosteroids (methylprednisolone), intravenous immunoglobulin (IVIg), or plasma exchange (PLEX). Second-line immunotherapy (rituximab, cyclophosphamide) is used when first-line treatment is inadequate. Tumour removal (when present) is critical for paraneoplastic forms. Seizure control, psychiatric support, and rehabilitation are important components of care. Dr. Jitendra Prasad Yadav (NMC 8029) provides evaluation and coordinates immunotherapy at Kathmandu Neurology Clinic, Durbar Marg, Opposite of Yak & Yeti Hotel.
| Treatment Phase | Therapies | Indications |
|---|---|---|
| First-line | Corticosteroids, IVIg, plasma exchange | Initial treatment for most cases |
| Second-line | Rituximab, cyclophosphamide | When first-line inadequate |
| Tumour removal | Surgical resection when cancer present | Critical for paraneoplastic forms |
| Supportive | Seizure control, psychiatric care, rehab | Symptom management and recovery |