Encephalitis Flashcards
What portion of encephalitis is viral?
20-50%
What is the major viral cause of encephalitis?
HSV (50-75%)
Major diagnostic categories for:
Acute/ Subacute Global Cerebral Dysfunction?
- Encephalitis
- Encephalopathy
- ADEM - Acute Disseminated Encephalomyelitis
Definition of Encephalopathy?
Altered consciousness
> 24 hours
Including lethargy, irritability or change in behaviour/ personality
Encephalopathy vs Encephalitis?
Encephalitis =
Encephalopathy + CNS inflammation
As evidenced by 2 of:
- fever
- seizures/ focal neurology
- CSF pleocytes (> 4)
- EEG findings
- Neuroimaging
Definition of ADEM?
Acute Disseminated EncephaloMyelitis
Focal neuro signs and rapidly progressive course (in generally a febrile patient)
Viral causes of encephalitis not restricted by location?
Herpes viruses: HSV 1, HSV 2, EBV, CMV, HHV 6, HHV 7
Enteroviruses: Coxsackie, echovirus, enterovirus (70 + 71), parechovirus, poliovirus
Paramyxoviruses: measles, mumps
Others (rare): influenza, adenovirus, parvovirus, rubella
Viral causes of encephalitis AUSTRALIA specific?
Murray Valley,
Kunjin,
Japanese Encephalitis,
Dengue
Typical signs of HSV encephalitis
frontotemporal signs
aphasia,
personality change,
focal seizures
Suggested Ix in Viral Encephalitis
FBE: lymphocytosis
CXR: findings in TB, HHV, other bugs
EEG: focal vs generalised
MRI Brain
LP
Autoimmune encephalitis name?
NMDA receptor encephalitis
Stages of NMDA receptor encephalitis
psychosis, memory deficits, seizures, and language disintegration
-> unresponsiveness + catatonic features often with abnormal movements, autonomic and breathing instability
Condition associated with NMDA receptor encephalitis?
Ovarian teratoma
More common in black women
Treatments for NMDA receptor encephalitis
Methylpred + IVIG or plasma exchange
+/- tumour removal (if present)
second line: rituximab/ cyclophosphamide
Treatment for ADEM
Early steroids
