CNS Infections Flashcards
What are the main classifications of CNS infections
Acute pyogenic meningitis (bacterial) Acute aseptic meningitis (viral) Acute focal suppurative infection (eg absess, subdural or extradural or extradural empyema) Chronic bacterial (TB) Encephalitis
What is the most cause of viral meningitis
enterovirus eg echo virus
what time of year does viral meningitis occur
late summer/autumn
How is viral meningitis diagnosed
viral stool culture
throat swab and csf for PCR
how is viral meningitis treated
supportive
What are the most common causes of viral enchephalitis
herpes simplex
herpes zoster
how is viral encephalitis treated
IV aciclovir
What are the typical clinical features of viral meningitis
insidious onset meningismus stupor coma seizures partial paralysis confusion psychosis speech, memory problems
What investigations should be done in suspected viral encephalitis
lumbar puncture
EEG
MRI
if LP contraindicated do a CT
what commonly causes bacterial meningitis in neonates
Group B strep
Listeria
E.coli
what causes bacterial meningitis in children
h. influenza
What is the most common cause in 10-21 year olds of bacterial meningitis
meningococcal
What is more commonly the cause of bacterial meningitis in adults over 21
pneumococcal> meningococcal
listeria is seen in elderly
What are the possible sequelae of menigitis
limb loss deafness blindness cerebral palsy quadriplegia mental impairment death
what causes of bacterial meningitis are seen in immunocompromised patients
S.pneumonia, s.aureus Listeria TB Mocardia asteroids Cryptococcus neoformans (AIDS)
What causes the symptoms in meningococcal meningitis
Neisseria meningitis endotoxin
How many types of h.influenzae are there and what type usually causes meningitis in young children
six
type b
what does h.influenzae require for growth
blood factors
What groups of people are more susceptible to pneumococcal menigitis
hospitalized patients CSF skull fractures diabetics alchoholics young children
What classification is listeria monocytogene
Gram positive bacilli
affects very young and old or immunocompromised
What is the antibiotic of choice to treat listeria
IV ampicillin/amoxicillin
resistant to ceftriaxone
What is cryptococcal meningitis
fungal - mainly in HIV
subtle presentation
aspetic CSF
what is the treatment of cryptococcal meningitis
IV amphotericin/flucytosine
fluconazole
what are the cardinal signs of bacterial meningitis
fever stiff neck alteration in consciousness headache vomiting photophobia confusion rash
