Exam 4 - CNS Infections Flashcards
what 5 things make up CSF composition/things you look at to figure out infection
Protein Glucose pH WBCs Fluid
CSF is made by ________
choroid plexus
Normal pH in CSF?
7.4
Normal Protein in CSF?
< 50 mg/dL
Normal Glucose in CSF?
50 - 66 % of serum glucose
Normal WBCs in CSF?
< 5 WBC/mL
normal fluid appearance CSF?
clear
3 layers of meninges?
dura mater
arachnoid
pia mater
BBB (blood brain barrier) or BCSFB (blood CSF barrier):
is 5000 x larger than the other
BBB is bigger
where is CSF found?
subarachnoid
BBB (blood brain barrier) or BCSFB (blood CSF barrier):
has ependymal cells to act as active transport system?
BCSFB
What characteristics make an abx penetration into the CSF easier:
Lipid phobic or phillic?
lipidphilic is better
What characteristics make an abx penetration into the CSF easier:
Ionized or unionized?
unionized is better
What characteristics make an abx penetration into the CSF easier:
low or high molecular weight
low is better
What characteristics make an abx penetration into the CSF easier:
high or low protein binding
low protein binding better b/c only free drug can penetrate
meningeal inflammation: help or hurt penetration into CSF?
help!
what drugs have therapeutic concentrations into CSF withOUT meningeal inflammation?
Acyclovir Chloramphenicol Fluconazole Ganciclovr Linezolid metronidazole rifampin FQs
(MR LAG FFC)
what drugs have therapeutic concentrations into CSF with meningeal inflammation?
PCNs 3rd/4th gen cephs aztreonam meropenem colistin vanc
(CV PAM 3rd/4th gen)
what drugs do not get into the CSF no matter if meninges are inflamed?
AGs Amphotericin-B beta lactamase inhibitors Some cephs (1st and 2nd gen) Clindamycin Tetracyclines (SCAT BA)
3 main ways bacteria gains access into the CSF?
hematogenous spread
contiguous spread
direct inoculation
what bugs are common cause of bacterial meningitis: In adults (30 - 50 years old)
S Pneumonaie, N meningitidis
what bugs are common cause of bacterial meningitis: older adults (>50 years old)
S pneumo
N mening
GNR
Listeria
3 most common causes of bacterial meningitis?
H. influenzae
Neisseria meningitidis
s. pneumoniae
3 most common signs of bacterial meningitis
fever
headache
stiff neck
CSF gets obtained via ______
need __#___ tubes for what tests?
LP: lumbar puncture
need 3 tubes: chemistry/hematology/microbiology