Encephalitis
Background
- Infection of brain parenchyma causing distinct neurologic abnormality
- Microbiology
- HSV, HZV, EBV, CMV, rabies, arboviruses (West Nile, St. Louis equine)
- Pathophysiology
- Gray matter is predominantly affected (cognitive / psychiatric signs, lethargy, seizure)
Clinical Features
- New psychiatric symptoms (HSV)
- Cognitive deficits
- Aphasia, amnesia, confusion
- Seizure
- Movement disorder (arboviruses)
- Fever and meningeal signs are almost always present
Diagnosis
- CT Head
- Medail temporal and inf frontal grey matter c/w HSV
- LP
- Bloody tap c/w HSV
DDX
- Meningitis
- SAH
- Lyme disease
- Brain abscess
- Bacterial endocarditis
- Toxic / metabolic encephalopathy
Treatment
- HSV encephalitis
- Acyclovir 10mg/kg q8hr
- HZV encephalitis
- Acyclovir 10mg/kg q8hr
- CMV encephalitis
- Ganciclovir 5mg/kg IV q12hr
Disposition
- Admit
Source
Tintinalli
