35 - CNS Infections Flashcards
Two most common community acquired meningitis organisms?
strep pneumo (pneumococcus) neisseria meningitidis (meningococus)
Most common bugs for neonatal meningitis?
group B strep
E. Coli
Listeria
Most common bug for immuno suppressed or elderly meningtits?
listeria monocytogenes
Most common post-trauma meningitis?
staph aureus
Gram negatives (E. Coli)
Pneumococcus
How does meningococcus spread?
respiratory droplets (epidemics in tight quarters) three foot rule for bed spacing.
What can fulminant meningococcus cause (outside the brain)?
Waterhouse-Friderichesen syndrome - hemorrhagic necrotic adrenals
What is Kernig’s sign?
patient supine with hip flexed 90 degs, knee cannot be fully extended
What is Brudzinski’s sign?
passive flexion of neck causes flexion of both legs and thighs
A cyst in brain on autopsy is opened and reveals a dark fluid that looks like crank-case oil. Diagnosis?
Craniopharyngioma of Rathke’s pouch.
You suspect meningitis in a patient. CSF shows high PMN count and normal glucose. DIagnosis?
possibly a ruptured craniopharyngioma causing an acute chemical meningitis.
What usually happens to serum Na levels in meningitis?
they drop becuase of accompanying septic shock and SIADH, there is water retention and increased ICP
What happens to INR and prothrombin time in meningitis?
they become elevated due to consumption of clotting factors in DIC
What happens to CRP in bacterial meningitis?
increased
What happens to procalcitonin level in bacterial meningitis?
increased.
If blood glucose is 100, what should normal CSF glucose be?
2/3 of blood so about 66.
What should be given first in bacterial meningitis?
steroids first! dexamethasone within 15 minutes of antibiotics.
Then give Vancomycin (for penicillin resistant pneumococcus),
a cephalosporin like ceftriaxone
ampicillin for listeria
doxycycline for rickettsia and rocky mountain spotted fever.
Acyclovir for viral
What adverse effect can meropenem have?
can cause seizures
What should be given to those who have been in close contact with a bacterial meningitis patient?
prophylaxis of rifampin or cipro