Week 8 - Bacterial Meningitis Flashcards
what can cause inflammation of the meninges (5)
- bacterial, viral, or fungal infection
- tumor mass
- hemorrhage
regardless of the cause, meningeal irritation often results in.. (4)
- sudden onset of severe headache
- back pain
- photophobia
- nuchal rigidity
what is nuchal rigidity
- hyperextended & stiff neck
what is the main difference between bacteria & viral meningitis
- bacterial = associated w significant morbidity, mortality & requires immediate antibiotic therapy
- viral = only requires supportive analgesic care
what is the most common cause of bacterial meningitis in neonates
- e.coli
what causes bacterial meningitis in neonates
- difficult delivery
- premature rupture of amniotic membranes
is e.coli gram (-) or (+)
(-)
what else can cause neonatal sepsis & meningitis
- group B streptococcus
are group B streptococcus gram (-) or (+)
(+)
what is the most common cause of bacterial meningitis in children & young adults
- Neisseria meningitidis (meningococcus)
is meningococcus gram (-) or (+)
(-)
how is meningococcus transmitted
- resp droplets
- carriers
what is the most common cause of bacterial meningitis in adults
s. pneumoniae
describe the pathogenesis of bacterial meningitis
- bacteria invades the host’s nasopharynx & causes bacteremia
- bacteria then invades the CNS
- and causes bacteria-induced injury to the cerebral endothelium (blood brain barrier) = meningeal invasions
- this leads to inflammation
what does the inflammation during bacterial meningitis cause (5)
- increased permeability of the blood brain barrier
- decreased CSF uptake
- cerebral edema
- increased ICP
- decreased blood flow
list manifestations of bacterial meningitis (12)
- severe HA
- back pain
- nuchal rigidity
- fever
- leukocytosis
- bacteria, proteins, and WBC in the CSF
- signs of increased ICP
- hydrocephalus
- seizures
- petechial rash
- kernig’s & bruzdzinskis signs
what is hydrocephalus
- accumulation of CSF within the ventricles
how does bacterial meningitis cause a petichial rash
- caused by an endoroxin released from neisseria & e.coli
- which triggers clotting, but not enough to form an actual clot, just consumes clotting factors & plts causing leakage of blood
what is kernig’s sign
- resistance to leg extension when lying down
what is bruzdzinski’s sign
- when neck flexion causes leg flexion
