CNS Infections - Exam 3 Flashcards
(108 cards)
What is meningitis? What is encephalitis? What is Meningoencephalitis?
Meningitis - inflammatory disease of the meninges surrounding the brain and spinal cord can be Bacterial, Viral or Fungal
Encephalitis - acute inflammation of the brain itself can be bacterial, Viral, (Parasitic, Fungi, Spirochetes)
Meningoencephalitis - inflammation of both the brain and the meninges
What are the 3 classic CNS infection s/s?
Fever
Headache
Altered mental status
What are the 3 meningeal signs?
nuchal rigidity
kernig
Brudzinski
**What is Kernig sign?
**What is Brudzinski sign?
What are some s/s of increased intracranial pressure?
Papilledema, poorly reactive pupils
Abducens (6th CN) palsy: horizontal diplopia
N/V
Bulging fontanelle (soft spot) in infants
What can a pt not due if they have abducens palsy?
eye that is affected, they cannot look laterally
can look medially but NOT laterally
What are the 3 layers of tissue that surround the brain and spinal cord?
Dura Mater- outermost layer - strong fibrous membrane
Arachnoid Mater - middle layer has cobweb like filaments that attach to the innermost layer
Pia Mater- innermost layer - a very thin and delicate membrane that is tightly to bound the surface of the brain
What layers contains blood vessels?
Subarachnoid Space - the space between arachnoid and pia mater
bacterial meningitis is an acute purulent infection of the ______ and the _______
arachnoid mater and the subarachnoid space
What give rise to the majority of bacterial meningitis cases?
Most cases result from previously colonized distant infection
from the Nasopharynx, respiratory tract, skin, GI tract and GU tract
In bacterial meningitis how does the bacteria have access to the CNS, give 2 ways it spreads? Which one is MC?
hematogenous spread - MC
direct contiguous spread from previous sinusitis, otitis media, mastoiditis, trauma, neurosurgical procedures
Where do newborns most common acquire bacterial meningitis?
pathogens colonized from the maternal intestinal or genital tract
or
transmitted from nursery personnel or caregivers at home
What pathogen is most common in adults with bacterial meningitis? healthcare acquired?
Streptococcus pneumoniae (~50-60%)
MC cause in adults >20 yrs old
S. aureus and coagulase-negative staphylococci-> think after a neurosurgery
What are the 3 MC pathogen for neonates (0-4 weeks old)?
GBS
e. coli
gram -negative bacilli
What are the top 3 MC pathogen for children older than 1 month?
Streptococcus Pneumoniae
Neisseria meningitidis¹
Haemophilus Influenzae type B (Hib)
What are the 4 MC symptoms associated with bacterial meningitis in adults? What is the classic triad? ___ out of 4 symptoms are present in most cases
Headache - MC
Fever - 2nd MC
Nuchal rigidity/meningeal signs
Altered mental status
2/4 present in most cases
What is nuchal rigidity?
pain with neck flexion
When is a meningococcal rash seen? Describe it
seen in septic meningitis with N. Meningitidis
maculopapular rash that become petechial and/or purpuric involving the trunk, LE, mucosal membranes, conjunctiva that DOES NOT BLANCH!!!
What are the historical red flags for bacterial meningitis?
Why would you want to order a coag profile in bacterial meningitis?
helps to differentiate who may need platelet or FFP after LP
Need to immediate collect _______ if you suspect bacterial meningitis
Immediate collection of blood cultures x 2 for gram stain, culture and sensitivity (C&S)
When working a pt up for bacterial meningitis, need prompt ________.
lumbar puncture
DO NOT delay LP for labs!
DO NOT delay empiric Abx therapy for LP or CT
**What are the guidelines to do CT scan BEFORE LP if:
Immunocompromised state
History of CNS disease: mass lesion, stroke, or focal infection
New onset seizure (within one week of presentation)
Papilledema
Abnormal level of consciousness
Focal neurologic deficit