Encephalitis

Question 1

Encephalitis overview

Answer 1

Inflammation of the brain parenchyma:
Viral and autoimmune

20,000 cases per year in us
likely higher

majority of cases are viral
herpes virus
Epstein Barr
arboviruses : spread to human from a arthropod mesquito or tick
WNV, with majority in the USA

Question 2

encephalitis clinical findings

Answer 2

Acute febrile illness:
Altered MS mild to coma

psychological changes:
Hallucinations, agitation, personality changes, behavior disturbances

Seizure disorder:
General or focal

Neurologic deficit: ( most common findings)
Aphasia, ataxia, upper or lower weakness, involuntary movement CN deficit

Hypothalamus- pituitary -axis
temperature dysregulation
Diabetes insipidus
SIADH

Question 3

Encephalitis work up

Answer 3

Lumbar puncture:
lymphocytic pleocytosis
mild elevated protien
normal glucose
persistent NEUTROPHILIA
consider bacteria infection

significant RBCs
hemorrhagic encephalitis rt HSV

Decrease CSF glucose
bacterial, fungal TB, or parasitic infections

Neuroimaging :
MRI brain
increased signal intensity

CT brain :
Focal areas of low absorption mass effect and contrast enhancement

EEG
strongly recommended
distinguish focal encephalitis vs encephalopathy

Question 4

ncephalitis treatment plan

Answer 4

supportive care management :
monitor ICP
fluid restriction
avoid hypotonic
suppress of fever
consult ID

Antiviral therapy:
empiric treatment Acyclovir 10mg kg Q 8 x 21 days
discontinue if no HSV
specific antiviral therapy
oral antiviral drugs have not been evaluated
glucorticortids and Acyclovir
some benfit