Viral Infections of the CNS Flashcards
What is the difference between meningitis & encephalitis?
- meningitis - inflammation of the leptomeninges
- encephalitis - inflammation of brain parenchyma
What is the term for the two inner meningeal layers?
leptomeninges
What is the term for the dura & arachnoid?
pachymeninges
What is the most common causative agent of meningitis? It is most common during what time of year?
enterovirus (coxsackievirus, echovirus, poliovirus)
summer months
What do we call any meningitis where the cause is not apparent after initial evaluation & CSF?
septic meningitis
What are the modes of transmission in which people can acquire causative agents of viral meningitis?
- direct contamination
- respiratory droplets
- fecal-oral contamination
What is the most common cause of acute encephalitis?
HSV1
What are the most important histories to consider when evaluating a patient with meningitis?
- recent illness/sick contacts
- immunizations
- contact w/ animals or insects
- recent travel; geographical location
What is the clinical presentation of a patient with viral meningitis? Treatment?
- younger age / IC
- Symptoms
- mild, flue-like
- headache (esp. bifrontal)
- fever
- photophobia
- nuchal rigidity
- malaise/change in mental status
- nausea
- Treatment
- typically self-limited; lasting <1week
- no treatment often needed
What type of cells are targeted by poliomyelitis virus?
Transmission?
motor neurons (anterior horn cells)
fecal-oral
What type of cells are targeted by varicella zoster virus?
peripheral sensory neurons
Clinical picture of a patient infected with EBV?
mononuceleosis-like picture w/ rash, pharyngitis, lymphadenopathy, splenomegaly
What type of cells are targeted by rabies virus?
brainstem neurons
What type of cells are targeted by west nile virus?
Transmission?
poliomyelitis (anterior horn cells)
summer months
What is the most common complication after a lumbar puncture?
post-lumbar puncture headache (PLPH)
Fill out the provided table for expected CSF profile for different etiologies
If you notice RBC in the CSF of on a lumbar puncture, you should think of what etiological cause?
HSV
What is the treatment for Viral meningitis?
- supportive
- monitor for seizure
- empiric treatment
- if meningoencephalitis, start antibiotics or acyclovir
What are the priimary findings with encephalitis?
- fever
- headache
- malaise
- altered mental status
HSV most commonly affects what areas of the brain in encephalitis?
temporal lobe
The Arboviruses most commonly cause what types of symptoms in encephalitis?
- Eastern Equine
- diffuse brain involvement (coma)
- WNV
- flaccid paralysis, fever HA
VZV most commonly cause what types of symptoms in encephalitis?
vascuopathy
What is the diagnostic workup for a patient with encephalitis?
- complete history & physical exam
- laboratories (serum)
- CT head (MRI brain), lumbar puncture +/- EEG
What is the management for encephalitis?
- antibiotics (empiric or organism specific)
- anticonvulsant therapy (if needed)
- intracranial hypertension directed therapy (if needed)
What are the clinical features seen in HSV encephalitis?
- change in consciousness
- fever
- change in personality
- Kluver Bucy Syndrome
- hyperphagia, hypersexuality, hyperorality
- headache
- seizures
- autonomic changes
- aphasia
- amnesia & hallucinations
What pathology is shown in the provided image? It is indicative of what etiological cause?
hemorrhagic necrosis of right temporal lobe
from HSV
What would you expect to see in the CSF studies from a patient with HSV encephalitis?
- HSV PCR
- +RBCs
What EEG changes would you expect to see in a patient with HSV encephalitis?
- diffuse slowing, focal temporal changes, & peeriodic lateralizing epileptiform discharges (PLEDS)
What is the treatment for HSV encephalitis?
IV acyclovir (10mg/kg q8x14-21 days)
start empiracally when suspected
prolonged oral course following IV course
Most relapses of HSV encephalitis occur within what timeframe of completing initial treatment?
3 months
What would you expect to see in a lumbar puncture of a patient with west nile virus?
abnormally high lymphocyte count or pleocytosis with hight total protein & WNV-specific IgM antibodies
What are the most common primary syndromes seen with HIV/AIDS in the CNS?
AIDS dementia complex (20%)
HIV myelopathy (20%)
HIV sensory neuropathy (30%)
Whta is Immune Reconstitution Inflammatory Syndrome & at what timepoint does it occur?
state of dysregulated, hyperinflammatory response against opportunistic infections that usually occur in first 6 mo. of treatment of HIV/AIDS patients
Is is common to detect SARS-COV-2 in CSF?
What are the nervous system manifestations of Covid-19?
no, it is rare
- CNS
- impaired consciousness
- acure cerebrovascular disease
- PNS
- skeletal muscle injury
What antibodies present in paraneoplastic autoimmune encephalitis can mimic viral encephalitis? They are each associate wtih waht cancers?
Hu, CV2/CRMP5, VGKC - lung
Ma2 - testicular
NMDAR - teratoma of overies
VGKC - thymoma
What is the name of the syndrome caused by paraneoplastic autoimmune that can mimic viral encephalitis?
limbic encephalitis
What is Creutzfeldt-Jakob Disease?
Transmissible spongiform encephalopathy caused by mis-folded prion proteins
What is the presentaiton of a patient with Creutzfeldt-Jakob Disease?
rapidly progressive dementia
What is the probable diagnostic criteria for Creutzfeldt-Jakob Disease?
neuropsychiatric disorder + RTQuIC in CSF/other tissue
OR
- Rapidly progressing dementia & 2/4 following:
- myoclonus
- visual or cerebellar signs
- pyramidal/extrapyramidal signs
- akinetic mutism
- often w/ exaggerated startle response
