Unit2_CNS Infections Flashcards
What is the “Classic Triad” ~w/ Bacterial Meningitis?
- Fever
- Headache
- stiff neck
+/- altered mental status
What patient population may lack the “Classic Triad” signs ~w/ bacterial meningitis?
Elderly and infants.
What is the median age of pt. with bacterial meningitis?
~42 years old
Bacterial Meningitis is the disease of the __________ space.
subarchnoid space
In Bacterial Meningitis, bacteria can reach the subarchnoid space how? (3)
- via bloodstream (most common)
- adjacent intracranial infection (sinusitis, mastoiditis, otitis)
- congenital, traumatic, or surgical defects in skull/spinal column.
What is the key diagnostic test for Bacterial Meningitis?
Lumbar Puncture (LP).
also need blood cultures and neuro-imaging (CT and MRI)
Complete LP immediately (no delay for neuroimaging) in all patients with suspected meningitis unless:
- decreased level of consciousness
- focal neurologic deficits
- papilloedema
- new onset seizures
- History of CNS disease or an associated condition (e.g. frontal
sinusitis) that increases probability of brain abscess/empyema. - Immunocompromised
- If above criteria are absent >97% have a normal CT
What should you do in Tx of Bacterial Meningitis is LP is delayed d/t to nuero-imaging?
Get STAT blood cultures & start empirical ABX therapy without delay and before LP.
What is the senstivity of a CSF gram stain?
60-90% (depends on who is reading the stain)
- H. Flu and Pneumococcus ~90%
- Meningococcus ~75%
- Gram negative rods ~50%
- Listeria ~33%.
What is the initial empiric Tx for Pt. w/ Bacterial Meningitis? (immunocompetent and normal renal function.
Neonates and infants (
Ampicillin (50-75 mg/kg every 6 hrs)
&
Cefotaxime (50 mg/kg every 6 hrs)
What is the initial empiric Tx for Pt. w/ Bacterial Meningitis? (immunocompetent and normal renal function.
Peds and adults 3-months to 50 years.
Ceftriaxone -or Cefotaxime
AND
Vancomycin
What is the initial empiric Tx for Pt. w/ Bacterial Meningitis? (immunocompetent and normal renal function.
> 50 years.
Ceftriaxone -or- Cefotaxime
AND
Vancomycin
AND Ampicillin
What is the initial empiric Tx for any Pt. with Nosocomial infection or immunocompromised, or recent head injury.
Vanco
AND
meropenum
+/- ampicillin
-Ampicillin is added to treat what bugs?
Listeria
___________ has activity against pseudomonas and other resistant gram-negative rods.
What is a common alternative to this drug?
Meropenem
Cefepime
__________ provides better coverage against penicillin/cephalosporin resistant
pneumococci and coagulase-negative and methicillin-resistant staphylococci as well as enterococcus
Vancomycin
What should pt. who have isolates resistant to penicillin or cephalosporins get?
repeat LP after 24-36 hours of Tx to document sterilization of CSF cultures.
What are is current recommendation for steroid use in the Tx of bacterial meningitis?
Give steroids 10-20min before the first dose of ABX.
Benefit is ONLY for pneumococcal
(Streptococcus pneumoniae) meningitis- consider discontinuing if another organism is ID-ed)
Headache, fever, meningeal irritation. Milder than with bacterial meningitis are the clinical features of what diz?
Viral Meningitis
What is the most important diagnostic test for Viral Meningitis?
PCR amplification
Routinely done for enteroviruses, HSV, VZV, CMV, and EBV.
In viral meningitis, _______ diagnostic of many aroboviruses (WNV)
CSF IgM
What are the Tx for the following viral meningitis?
- HSV
- VZV
- HIV
- CMV
- flu
- Enterovirus
- WNV
- HSV = Acyclovir
- VZV = Acyclovir
- HIV = Anti-retrovirals
- CMV = Foscarnet, gancicovir, cidofovir
- flu = Rimantidine
- enterovirus - Pleconaril
- WNV = supportive Tx
_______________ is an infection of brain tissue rather than just subarachnoid space
(meningitis). Signs/symptoms usually much more extensive than for meningitis.
Viral encephalitis
What are the clinical PPT of Viral encephalitis?
A. Common: Altered consciousness, fever, and headache.
B. Seizures and focal neurological signs/symptoms are common:
- personality change, alteration in mental status/level of consciousness (75-95%)
- aphasia (65-75%)
- hemiparesis (30-40%)
- ataxia (40%)
- cranial nerve palsies (30- 35%)
- visual field loss (10-15%)
What is the most common cause of arboviral encephalitis in the USA?
West Nile Virus (WNV)
How do you diagnose Viral Encephalitis?
A. CSF pleocytosis.
B. EEG abnormal in 60-90%.
C. CT and MRI are helpful in identifying focal encephalitis (e.g. herpes) and in
excluding other diseases that can mimic encephalitis. MRI is more sensitive
than CT.
D. PCR amplification of viral nucleic acid from CSF is the diagnostic
procedure of choice for HSV, VZV, CMV, EBV, and enteroviruses.
E. Detection of WNV IgM in CSF is diagnostic of WNV encephalitis and
more sensitive than PCR.
F. “Coming Soon”: CSF Biofire Filmarray Meningitis/Encephalitis Panel
What are the Tx for the following viral meningitis?
HSV
HSV = Acyclovir
What are the Tx for the following viral meningitis?
VZV
VZV = Acyclovir
What are the Tx for the following viral meningitis?
HIV
HIV = Anti-retrovirals
What are the Tx for the following viral meningitis?
CMV
CMV = Foscarnet, gancicovir, cidofovir
What are the Tx for the following viral meningitis?
flu
flu = Rimantidine
What are the Tx for the following viral meningitis?
Enterovirus
enterovirus - Pleconaril
What are the Tx for the following viral meningitis?
WNV
WNV = supportive Tx
