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central nervous system
includes brain,spinal cord and meninges aka CNS
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peripheral nervous system
- aka PNS
- includes cranial and spinal nerves
-
defenses of the CNS and PNS
- bony casings
- cerebral spinal fluid-cushoins
- blood brain barrier- difficult for organisms to get in
- phagocytic functions- wbc eat
- macrophages
-
is ther normal biota in CNS or PNS
NO
-
meninigitis
- inflammation of the meninges caused by baterica-most serious
- virues
- fungi
-
how do you diagnose meningitis
lumbar puncture for cerebral spinal fluid to test
-
symptoms of meningitis
- headache
- painful or stiff neck
- fever
- increased WBC in the CSF
-
bacteria's that cause mennigitis
neissera meningitidis
streptococcus pneumonia
haemophilus influenza
listeria monocytogenes
-
neissera meningitidis
- aka meningococcus
- most serious form
- enters via nasal route
-
streptococcus pneumonia
- aka pneumococcus
- most frequent cause of community acquired meningitis
- very severe
-
haemophilus influenza
severe
-
listeria monocytogenes
- mild in adults
- contracted from contaminated dairy,meat, poultry or cantaloupe
-
fungal causes of meningitis
crytococcus neoformans
coccidioides immitis
-
crytococcus neoformans
- more chronic
- gradual onset of symptoms
- common in aids community
- can disseminate to the skin,bones and viscera
-
coccidioides immitis
- found in soil
- causes system infections
-
viral couses of meninigtis
- caused by enterococcus aka herpes virus 90%
- majority found in children
- aka aseptic meningitis
- no bacteria or fungi found in CSF
-
neonatal meningitis
- transmitted by mother to childeither utero or birth canal
- caused by streptococcus agalactia
- or eschericha coli -severe causes brain damage
-
meningoencephalitis
- caused by naegleria fowler
- and acanthamoeba
-
naegleria fowler
amoeba forced into nasal passageway fom swimmingf in infected water
causes death in weeks
-
acanthamoeba
- enters broken skin through contaminated waters
- chronic
-
can any organism that cause meningitis cause encephalitis?
YES
-
acute encephalitis
caused by viral infection
symptoms include behavoir changes,confusions,decreased consciousness, seizers
-
organisms that cause encephalitis
- arbovirus
- herpes simplex virus
- jc virues
-
arbovirues
- borne by insects aka arthopod vectors)
- most feed on the blood host
-
herpes simplex viruse
occurs in newborns by mothers with this disease
-
jc viruse
rare but seen in aids patients
-
subacute encephalitis
symptoms take longer to show
caused by toxoplasma gondi-protozoan parasite
severe if transmitted to fetus
can be transferred by litter box
cyst can be ingested by contaminated meat
seen in aids pts
-
subacute sclerosing panencephalitis
- aka sspe
- occurs years after initial measels episode
- caused by direct viral invasion of neural tissue
- causes progressive neural tissue degeneration
-
prions
- proteinaceous infectious particles
- cause 9 animal diseases
- inherited and transmissble by ingestin of infected meat
- passed by transplant or surgical instruments
- possible by gecetic transmission
-
prions are caused by
spongiform encephalopathy
sheep scrapie
bovine spongiform encephalapthy
-
spongiform encephalapathy
neurological disorder
-
sheep scrapie
- neuro disoreder in sheep
- caused by infected food fed to cows aka mad cow disease
-
bovine spongiform encephalapathy
- cj diease
- can last years
- progressive dementia and memory loss
-
rabies
- slow progressive zoonotic disease
- characterised by fatal encephalitis
-
average incubation time of rabies
1-2 months
-
prodromal phase of rabies
- fever
- nausea
- vomiting
- headache
- fatigue
-
treatment of rabies
passive and active immunology
-
furious rabies
- periods of agitation
- disorientation
- siezures
- twitching
- spasms in the neck
- pharyngeal muscles leads to hydrphobia
- results in death unless vaccinated proior to symptoms
-
dumb rabies
- pt is paralyzed
- disorientated and stuporous
- results in death unless vaccinated prior to symptoms
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