encephalitis

Question 1

inflammation of brain parenchyma

Answer 1

encephalitis

Question 2

what causes encephalitis?

Answer 2

viruses is by far the main cause of encephalitis

ocassionally bacteria is the culprit

Question 3

what is the difference between encephalitis and meningitis?

Answer 3

both are associated with lethargy and headache but meningitis has no alteration of mental status

also more common with encephalitis is seizures, flaccid paralysis and paresthesia

Question 4

major routes of entry to CNS (3)

Answer 4

1. olfactory nerve pathway
2. peripheral nerve pathway
3. hematogenous spread

Question 5

most pathogens enter hematogenous through (2) ways

Answer 5

1. enter CSF via choroid plexus

2. direct infection of endothelial cell of brain vessels

Question 6

Herpes simplex enters the CSF is through

Answer 6

direct peripheral neuronal spread

Question 7

Two ways pathogens do damage in CSF

Answer 7

1. Direct damage by viral invasion of neurons
   
   2. Post-infectious/ADEM- host inflammatory response that then results in damage due to influx of inflammatory cells, swelling, etc.

Question 8

hallmark of encephalitis

Answer 8

altered mental status

Question 9

Most causes of encephalitis cannot be distinguished by CSF profile!!

Answer 9

so true

Question 10

the only one encephalitis virus that can be treated

Answer 10

Herpes viruses

Question 11

Which herpes virus is more common to cause enccephalitis?

Answer 11

HSV-1

Question 12

entry of HSV-1 to CNS? what type of encephalitis do we get?

Answer 12

from peripheral nerves causing a acute focal encephalitis with temporal lobe predilection

Question 13

most sensitive way to pick-up differences in temporal lobe

Answer 13

EEG

Question 14

diagnosis of HSV encephalitis

Answer 14

CSF PCR is highly sensitive and specific

***brain biopsy used to be the gold standard but it is not done anymore

Question 15

first line treatment of HSV encephalitis

Answer 15

acyclovir

Question 16

eastern equine encephalitis (EEE) end stage

Answer 16

humans and horses

Question 17

entry of EEE

Answer 17

hematogenous route

Question 18

Most severe arthropod-borne illness in North America

Answer 18

EEE

Question 19

diagnosis of EEE

Answer 19

IgM ab to the virus in CSF and neutralizing ab

Question 20

RNA flavivirus

Most common vector borne cause of encephalitis in US today. Cases began in U.S. in 1999

Answer 20

west nile virus

Question 21

west nile virus is different due to one symptom we dont tend to see with other encephalitis

Answer 21

polio-like syndrome—> flaccid paralysis

Question 22

west nile virus has a direct patient to patient transmission

Answer 22

nope, no direct. rarely can be transmitted by non-vectored means

Question 23

west nile virus diagnoisis

Answer 23

serology (IgM)

Question 24

2 forms of rabies but both lead to death

Answer 24

1. encephalitic rabies

2. paralytic rabies

Question 25

type of rabies:

• ascending paralysis
• later cerebral involvement

Answer 25

Paralytic Rabies

Question 26

type of rabies:

Agitation
Hypersalivation
Hydrophobia
Bizarre behavior, disorientation, stupor, coma, death

Answer 26

encephalitic rabies

Question 27

CNS pathology in rabies

Answer 27

negri bodies – eosinophilic cytoplasmic inclusions in neurons represent accumulated viral particles

Question 28

rabies prevention

Answer 28

1. neutralize virus with human rabies immune globulin

2. rabies virus specific immune response induction (vaccine)