- disease which produce antibodies against neuronal cell surface proteins
- sometimes responds to immunoglobulins
Types of Autoimmune Encephalopathy
- possible autoimmune encephalitis
- probable antibody negative encephalitis
- definite antibody positive encephalitis
Anti N-methyl D-Aspartate Receptor Encephalitis
- 2nd most common autoimmune encephalopathy
- can occur at any age, but most common in pediatric age groups
Clinical features
- Psychiatric manifestations (initial)
- anxiety
- agitation
- delusion
- bizarre behavior
- labile mood
- catatonia
- memory deficit
- aggression
- sleep disturbance
- Additional manifestations (in few weeks)
- decreased level of consciousness
- seizures
- oral dyskinesia
- choreo-athetoid movement
- autonomic instability
- bradycardia
- fluctuation of blood pressure
Labs
- MRI
- non specific cortical and sub-cortical T2 flair
- if white matter changes predominant - suspect overlapping demyelinating syndrome
- CSF
- moderate pleocytosis
- oligoclonal bands
- NMDAR antibodies
- EEG
- focal or diffuse slowing of activity in delta and theta ranges
- Extreme delta brush - characterized by beta-delta complexes
- association with tumor (teratoma) in 40% of female older than 12
- Association with HSV1
- doubtful association with mycoplasma, HHV 6, enterovirus, COVID 19 and Japanese Encephalitis
Treatment
- Tumor removal and Immunotherapy
- Immunotherapy
- corticosteroids
- IVIG
- plasma exchange
- Rituximab
- 80% fully recover
- 15% relapse
- 5% mortality