Flashcards in CNS Infections Deck (71):
1
4 Signs of increased ICP
-papilledema
-Abducens (6) palsy
-bulging fontanelle
-cushings reflex
2
List the cushings reflex triad
-HTN
-bradycardia
-irregular respiration
3
Are Kernigs and Brudinskis sensitive or specific for meningitis?
-both are very specific but not sensitive (5%, 95%)
4
Which clinical meningitis sign is most sensitive?
-nuchal rigidity
(but still not very sensitive, 30%)
5
CNS infection- pertinent labs
-CBC
-Complete Chemistry
-PT/PTT
-HCG
-blood + urine cultures
6
When is it appropriate to scan prior to LP?
-localizing signs
-AMS
-seizures
-signs of increased ICP
7
What are the uses of the four tubes drawn during LP?
1- glucose and protein
2- cell count
3- gram stain, routine culture
4- viral studieqs, VDRL
8
What should never be tested from tube 1 in LP?
-culture and gram stain, skin flora in tube one
9
How quickly is CSF normally replenished?
-half mL per minute
normal volume = 140 mL
10
Normal CNS glucose levels
2/3 serum glucose, 1/3 or less very sensitive for bacterial meningitis
11
How can protein levels be evaluated in traumatic tap?
-protein up 1 for every 700 RBCs
12
How many mononuclear WBCs are typically in CSF?
0-5
13
Proper position for LP opening pressure determination?
-lateral decubitus, not prone
14
What type of meningitis has normal opening pressure?
-fungal CAN be normal or low, other types at least slightly elevated
15
What type of meningitis has normal glucose?
-viral, all others have low glucose, esp bacterial
16
What type of meningitis has normal protein?
-viral, all others have high protein, esp bacterial
17
What type of meningitis involves RBCs in CSF?
-Bacterial
18
List the normal number of WBCs in CSF for each meningitis etiology:
-bacterial: over 200
-viral: 50-200
-fungal: 30-50
-TB: 20-30
19
Cell type predominant in CSF for bacterial, viral, fungal and TB meningitis
-mono except in bacterial = PMNs
20
Viral meningitis:
frequent bugs
-adeno
-entero
-arbo
21
Viral meningitis:
-typical months
-typical length
-summer
-week
22
Frequent bacterial meningitis bug across all age groups
-strep pneumo
23
Top 2 bugs in neonatal meningitis + empirical treatment
-1 GBS
-2 Listeria
-amp & gent
24
Top 2 bugs in 1-23 month olds + empirical treatment
1- strep pneumo
2- n men
ceftriaxone + vanc
25
Top 2 bugs in 2-18 year olds + empirical treatment
1- n men
2- strep pneumo
(GBS, Listeria also possible)
ceftriax + vanc + amp
26
19-59 top 2 meningitis bugs + treatment
-strep
-n men
ceftriax + vanc
27
Top 2 bugs in elderly meningitis + empiric treatment
-Strep pneumo
-Listeria
-ceftriax, vanc, amp
28
Treatment for GBS meningitis (2)
-amp
or
-pen G
29
Treatment for neisseria meningitis (2)
-amp
or
-ceftriaxone
**may add dexamethasone
30
Strep pneumo meningitis treatment
-ceftriax + vanc if penicillin resistant
31
Listeria treatment in meningitis
amp and gent
32
Treatment for gram - meningitis
-ceftriaxone or cefotaxime
33
Px for n meningitis
-rifampin 2 weeks or ceftriax one dose IM
34
Long term effects of bacterial meningitis
-hearing loss
-learning disability
-epilepsy
-hydrocephalus
35
Mortality rate encephalitis
10%
36
Common encephalitis origins
HSV1
arboviruses (west nile, eastern equine)
enterovirus (polio)
37
Nonviral causes of encehpalitis in the immunocompromised
-toxoplasmosis
-aspergillosis
38
When bacterial infections involve the brain they are called ____
cerebritis vs abscess depending on whether capsule exists
39
At what CD4 count is AIDs patient at risk of encephalitis?
200
40
Risks for encephalitis aside from immunosupression
-travel
-bats, mosquito exposure
(in endemic areas)
41
Encehpalitis workup: how do labs differ from meningitis workup?
-send CSF for cytology to evaluate for cancer cells
42
Basic lab added to encephalitis workup
UA
43
Imaging most sensitive for diagnosing viral encephalitis
-T2 MRI.
44
Treatment for HSV, VZV, EBV encehpalitis
IV acyclovir
45
Treatment for CMV encephalitis
ganciclovir, foscarnet
46
Treatment for lacrosse california encehpalitis
Ribaviron
47
Viral encephalitis with highest number of neuro sequelae
eastern equine (80%)
48
Otitis/mastoiditis:
how commonly do they cause abscess?
Where do they most commonly form abscess in brain?
cause of 33% abscesses
MC temporal/cerebeller
49
Common otitis/mastoiditis organisms?
-strep
-bacteroides
-pseudomonas
50
Sinusitis:
-what bugs are implicated
-where might they form cerebral abscess?
-staph aureus
-haemophilus
51
How commonly are brain abscesses a result of hematogenous spread?
25%
52
MC symptom of brain abscess?
-#1 headache
60% focal deficits, 35% seizure
53
Typical antibiotics for abscess?
cephalosporin
metronidazole
54
Neurosurg abscess drugs
ceftaz and vanc to cover staph and pseudomonas
55
When should steroids be given for abscess?
only if there is significant edema
56
MC cause subdural empyema
extension of sinus infection or meningitis
57
Treatment for subdural empyema
-burr hole + drainage
-cefotaxime + metronidazole
58
Cause of epidural empyema
#1 sx/skull fracture
-also mastoiditis, sinusitis, otitis
59
Treatment epidural empyema
-drainage
-vanc
-metronidazole
60
#1 cause meningitis in AIDs patients
cryptococcus
61
C. neoformans animal assc
pigeon soil --> inhaled --> blood --> meninges
62
Stain for cryptococcus
india ink
63
Treatment for cryptococcus
amphotericin
fluconazole
64
At what CD4 count is toxoplasmosis a concern in HIV patients?
200
65
Toxo:
How is diagnosis made?
MRI
66
How is toxoplasmosis treated?
sulfadiazine
pyrimethamine + leucovorin
67
What is toxo px for AIDs patients
TMP SMX daily until CD4 is greater than 200
68
What part of the brain is most susceptible to toxo?
basal ganglia
69
Bug assc with neurocysticercosis
T solium
70
Dx neurocysticercosis
MRI/CT
71