CNS Micro Flashcards
are levels of complement low or high in CNS?
low
what cell of the CNS regulates the immune response?
astrocytes
what cell of the CNS is a macrophage?
microglia
what cytokine do astrocytes make?
TGF-b
can T cells enter the BBB if they are unactivated?
no must be activated to enter
what is the rule for B cell to enter BBB?
BBB must be inflamed
what antibody is mainly in the CNS?
IgG
what are three child causes of bacterial meningitis?
E coli
Group B strep
listeria monocytogene
what are two adult causes of bacterial meningitis?
strep pneumo and neisserie meningitidis
what is the structure of E coli?
encapsulated rods
is E coli gram pos or neg?
negative
if H flu gram neg or pos?
negative
what is the structure of H flu?
encapsulated coccobacilli
what is structure of streptococcus agalactiae?
encapsulated cocci in chains
is strep agalactiae gram neg or pos?
pos
what type of hemolysis in strep agalactiae?
beta hemolytic
what is structure of strep pneumo?
encapsulated diplococci
is strep pneumo gram neg or pos?
pos
what type of hemolysis in strep pneumo?
aplpha
what is structure of staph A?
encapsulated cocci in clusters
is staph A gram neg or pos?
pos
what type of hemolysis in staph A?
beta hemolysis
what is the structure of mycobacterium TB?
acid fast bacilli
what is structure of listeria monocytogenes?
facultative intracellular rods…no capsule
is listeria monocytogenes gram neg or pos?
pos
what is structure of neisseria meningitidis?
encapsulated diplococci
is neisseria menigitidis gram neg or pos?
neg
where is neiserrie menigitidis commonly found?
respiratory tract
what is the yeast that can cause menigitis?
cryptococcus neoformans
what is the structure of cryptococcus neoformans?
encapsulated round yeast
where do we pick up cryptococcus neoformans?
inhaled pigeon shit
what is the one type of infection that leas to a cloudy colored CSF?
bacterial
what three infection types lead to elevated opening pressure of subarachnoid space?
bacterial
fungal
TB
what infection type does not lead to elevated opening pressure
viral
what cell type is elevated in bacterial menigitis?
PMNs
what cell type is elevated in viral meningitis?
lymphocytes
what happens to protein in bacterial meningitis?
protein is up
what happens to glucose in bacterial, Tb and fungal meningitis?
is down because immune cells using it up to fight
what was the issue with the neisseria mengitidis vaccine originally?
it did not cover the B group capsule so you could still get infected with that strand
what does the new N. meningitidis vaccine cover?
the B group capsule
what type of vaccine is the N. meningitidis B?
protein based
meningococcal meningitis leads to what in CSF?
super high levels of the bug, cloudy CSF, elevated opening pressure, high PMNs, elevated protein and decreased glucose
what happens to skin with meningococcal meningitis?
get non blanching petechial rash
how does listeria get into CNS?
retrograde transmission along the cranial nerves, especially those in oral cavity
what is abnormal about CSF in listeria meningitis?
not usual findings…no cloudiness and no PMN elevations
what is listeria meningitis associated with?
atypical sub acute course…leading to abnormal movements, seizures and loss of consciousness
what is the structure of enteroviruses?
SS +RNA
are enteroviruses enveloped?
non enveloped
what enteroviruses can lead to CNS infection?
polio and coxsackie viruses
what is transmission of polio virus?
fecal to oral
how does polio spread to CNS?
via motor neurons in the GI tract
what are the two vaccines for polio? which is used now?
SAlk and Sabin…salk used now
what virus associated with animals is common to cause CNS issues?
rabies virus
what is structure of rabies virus?
ss negative sense RNA
is rabies virus enveloped?
enveloped
how does rabies virus reach the CNS?
retrograde movement from bite site along a peripheral nerve
what is the histologic finding in rabies?
Negri bodies
what do negri bodies look like?
cytoplasmic inclusions in neurons…little bumps
what are symptoms of rabies?
acute progressive encephalitis….fever headache dysphagia
what are the viruses associated with the togaviridae class that can affect CNS?
eastern/western equine enceph
venzuelan equine enceph
what are the viruses associated with flaviviridae that can affect CNS ?
west nile and zika
what is structure of viruses in flaviviridae and togaviridae families?
pos sense ssRNA with envelope
what is gene type of herpes viruses?
ds DNA
are herpes viruses enveloped??
yes they are
what are the two herpes simplex viruses that can lead to CNS issues?
HSV1 and HSV2
who is at risk for severe disease from HSV1/2?
neonates with mother who has primary infection late in pregnancy
where does HSV1 and 2 remain latent?
in neuronal cell bodies
how do HSV1 and 2 get into neuronal cell bodies?
break through keratin in skin and do retrograde transport along neurons
what can HSV1/2 cause in CNS?
only encephalitis…no meningitis
how does HSV1/2 spread?
anterograde transport from neuron cell bodies leads to viral replication in epithelial cells
what can happen to eye in HSV infection?
corneal scarring
what can induce HSV1 reactivatiom?
stress…nerve damage…sunlight..illness
what does HSV1 reactivation look like on skin?
vesicles on erythematous base
HSV meningitis has what special thing in CSF?
RBCs!! with elevated lymphocytes too
where does latency of VZV occur?
in ganglia of cervical, lumbar and thoracic ganglia
reactivated VZV looks like what? is called?
shingles…dermatomal rash
what is drug used to treat HSV?
acyclovir
what must happen to acyclovir when you give it?
needs to be activated
what activates acyclovir?
HSV thymidine kinase…adds to its specificity
what is the more active form of acyclovir that you can give?
valacyclovir
what is the drug used to treat CMV?
ganciclovir
how does ganciclovir work?
activated by CMV kinase and chain termination of DNA synthesis
