CNS Infections II Flashcards
where does Haemophilus influenzae get its virulence
pili, LPS, capsule (polyribitol phosphate)
biology of heamophilus influenzae
non motile gram neg rod, fastidious [uses X (heme) and V (NAD) factor]
clinical features of h. influenzae
- slower onset (3-4 days)
- follows: nasopharyngitis, sinusitus, otitis media
- 1/3 survivors have neurological sequel
prevention of haemophilus influenzae
vaccine: herbix
problem with vaccination of h. influenzae
it is specific for the capsule of h. influenzae but new strains are now unencapsulated
who gets the listeria monocytogenes strain of meningitis
– Infants
– Adults >60y, alcoholics, cancer patients, renal transplant
-those who drink unpasteurized milk
biology of listeria monocytogenes (include virulence factor)
gram positive rod
virulence factors: internalin A and B, listeriolysin O
functions of internalin A and B and listeriolysin O
internalins - helps bacteria attach to host
listerolysin - form spores that help bacteria invade cells
clinical features of listeria monocytogenes
– Subclinical-gastrointestinal like
– Neonatal
– Immunocompromised
transmission of strep agalactiae
it is seen in newborns so vertical transmission from pregnant women who 15-35% of them are asymptomatic
Facultative Gram-negative bacilli
Klebsiella, E. coli, S. marcescens, P. aeruginosa
how does one get the facultative gram neg bacilli
head trauma or neurosurgery
how does one get a staphylococci CNS infection
early post neurosurgical/post-trauma hence why it is so uncommon
underlying conditions that lead to staphylococci CNS infections
– Diabetes mellitus
– Alcoholism
– Chronic renal failure (hemodialysis)
how does staph epidermidis get to the CNS
uses CSF shunts
what is a health care related CNS infection
MRSA
treponema pallidum can lead to what CNS infections
syphilis and spirocheteal meningitis
clinical neurosyphilis
– Syphilitic meningitis (0.3-2.4% untreated cases)
– Meningovascular syphilis
– Parenchymatous neurosyphilis
– Gummatous neurosyphilis (rare)
Borrelia burgdorferi can lead to what infection
Lyme infection
special feature of borrelia burgodorferi
clinical features of borrelia burgodorferi
spirochete
2-10 weeks post erythema migrans
symptoms of viral causes of meningitis
- acute benign, self limiting, monophasic
- cranial neuropathy and raised intracranial pressure
most common cause of viral meningitis in US
enterovirus
pathogenesis of viral causes of meningitis
mucosal surface colonization RTI/GIT –> viremia –> CNS invasion –> virus spread within the CNS
who gets non polio enterovirus
infants and young children with no previous exposure and immunity
thought it is part of adult normal flora
