8 - Meningitis Flashcards
What are the risk factors for meningitis ?
- neonates, advanced age, pregnancy (prob a type of immune deficiency)
- nasopharyngeal colonization with N. meningitides, S. pneumonia, H. influenzae
- prior URTI, cochlear implants
- cranial anatomical defects, trauma, fracture, neurosurgery, prosthesis, drains
- immunocompromised
Describe the pathophysiology of meningitis
- entry of multiplication of bacteria in CSF
- lysis of bacteria
- increases coagulation
- decreases fibrinolysis
- BBB permeability
- metabolic disturbances
- brain damage
- increased intracranial pressure
What are the most likely pathogens for meningitis ?
N. meningitidis
Strep pneumoniae
H. flu
L. monocytogenes (sandwich meat/pregnant ppl)
What are the most likely pathogens according to patient age:
Neonates ?
Neonates < 1 month:
S. agalactiae
E. coli
(less commonly - Strep pneumoniae, L monocytogenes)
What are the most likely pathogens according to patient age:
Children
N. meningitidis
S. pneumoniae
(H. flu if unvaccinated)
What are the most likely pathogens according to patient age:
Adults
N. meningitidis
S. pneumoniae
What are the most likely pathogens according to patient age:
Pregnancy, advanced age > 60, immunocompromised
L. monocytogenes
What are the most likely pathogens according to patient age:
Immunocompromised, HCA
S. aureus
GNB (gram negative bacilli)
N. meningitides more common in _______
children
S. pneumoniae is more common in ________
elderly
nuchal
pertaining to the spinal cord
What are the 3 most common clinical signs of meningitis?
1) Fever > 40 in 90% of ppl
2) Nuchal rigidity or neck stiffness (80%)
3) CNS (80%) such as headache, photophobia, confusion, seizures, coma
- 95% of cases with >2
- 50% of cases with all 3
What are some non-specific symptoms of meningitis?
- fever
- seizures
- respiratory distress
- septic shock in neonates
What sign is HIGHLY suggestive of meningococcal infection?
RASH
-petechial or purpural rash present in >50% of meningococcal infections
What are the complications that can arise from meningitis? (3)
1) Herniation - diffuse swelling, hydrocephalus
2) Infarcts - inflammatory occlusion of basal arteries
3) Seizures - cortical inflammation
see page 8 for mortalities
okay
A 21 yr old female gets meningitis - what are the most likely pathogens based on her age ?
- N. Meningitidis
- Strep pneumo
List 3 antimicrobial fundamentals in treating meningitis?
1) Early, prompt initiation
2) CSF penetration (antibiotic size, lipophilicity, ionization, protein binding, barrier inflammation)
3) Rapid sterilization
Delays in administration of antibiotic are associated with ______ from adult acute bacterial meningitis
mortality
Why do we depend on inflammation in meningitis ?
We need to depend on the inflammation that occurs in these tight junctions that allow the drug to get through the BBB and the BCSFB.
Ceftriaxone is _% free
5
*this 5% that is free is therapeutic for meningitis
Which drugs are able to achieve therapeutic CSF concentrations with or without inflammation
- Chloramphenicol
- Metronidazole
- Rifampin
“Connie Myers Rules” lol
Which drugs only achieve therapeutic CSF concentrations WITH inflammation?
- Penicillins
- 3rd GC & Cefuroxime
- Daptomycin
- Fluoroquinolones
- Linezolid
- Meropenem
- TMP-SMX
- Vancomycin
Which drugs will not achieve therapeutic CSF concentrations ?
- Aminoglycosides
- other Cephalosporins
Empirical age based formula for meningitis:
< 1 month
Cefotax (covers strep and pneumoniae) \+ Amp (covers listeria) \+/- Gent (this doesn't get into CSF ! sometimes penicillin can be less effective against GAS so Gent is added on)
Why not Ceftriax?
- cannot be given with calcium
- can displace bilirubin
Empirical age based formula for meningitis:
1 month to 17 years
Cefotax / Ceftriax (covers strep and pneumoniae)
**Ceftriax can be used here !
+
Vanco (covers PRSP)
*This is only added on for the initial day or two until you know what the bug is
Empirical age based formula for meningitis:
18 - 50 years
Cefotax / Ceftriax (covers strep and pneumoniae)
+
Vancomycin (covers PRSP)
*This is only added on for the initial day or two until you know what the bug is
Empirical age based formula for meningitis:
> 50 years
Cefotax / Ceftriax (covers strep and pneumoniae)
+
Vancomycin (covers PRSP)
*This is only added on for the initial day or two until you know what the bug is
+
Amp (covers L. monocytogenes)
Treatment for:
HCA meningitis
Mero (to cover all the other possible drugs) or Ceftaz
+
Vanco (covers PRSP)
*This is only added on for the initial day or two until you know what the bug is
Treatment for:
Immunocompromised
Mero (to cover all the other possible drugs)
+
Vanco (covers PRSP)
*This is only added on for the initial day or two until you know what the bug is
+
Amp (to cover L. monocytogenes)
Meningitis dose:
Cefotaxime
2 g q4h
Meningitis dose:
Ceftriaxone
2g q12h
Meningitis dose:
Ampicillin
2g q4h
Meningitis dose:
Vanco
15-20 mg/kg q8h
troughs 15-20 mg/L
Meningitis dose:
Meropenem
2g q8h
Meningitis dose:
Ceftazidime
2g q8h
Meningitis dose:
Penicillin G
4 MU q4h
Max dose on sheet!
Meningitis dose:
Rifampin
600 mg q24h
same as on sheet, don’t need to memorize!
Meningococcal meningitis:
Peak in ?
late winter and early spring
Meningococcal meningitis:
Predominantly Group __
B
Meningococcal meningitis:
Peak incidence in who ?
children and young adults
60% of cases in 2-18 years
Meningococcal meningitis:
Colonization in _____% of adolescents and adults
10-20
Meningococcal meningitis:
Natural immunity in __% by 2 years of age
80%
N. meningitidis:
Pen-S
1st line ?
Pen G or Amp
N. meningitidis:
Pen-S
Alternatives ?
Cipro
N. meningitidis:
Pen-RS
1st line ?
Cefotax / Ceftriax
N. meningitidis:
Pen-RS
Alternatives ?
Chloram
N. meningitidis:
Duration of treatment ?
5-7 days
S. pneumoniae:
Pen-S
1st line ?
Pen G or Amp
S. pneumoniae:
Pen-S
Alternatives ?
Levo/Moxi +/- Vanco
[Chloram, Linezolid]
S. pneumoniae:
Pen-R
1st line ?
Cefotax / Ceftriax
S. pneumoniae:
Pen-R
Alternatives ?
Levo/Moxi +/- Vanco
[Chloram, Linezolid]
S. pneumoniae:
3rd GC, MIC >1
1st line ?
Cefotax / Ceftriax
+
Vanco
S. pneumoniae:
3rd GC, MIC >1
Alternatives ?
Levo/Moxi +/- Vanco
[Chloram, Linezolid]
S. pneumoniae:
3rd GC, MIC >2
1st line ?
Cefotax/ Ceftriax \+ Vanco \+ Rifampin
S. pneumoniae:
3rd GC, MIC >2
Alternatives ?
Levo/Moxi +/- Vanco
[Chloram, Linezolid]
S. pneumoniae:
Duration of therapy ?
10-14 days
L. monocytogenes:
1st line ?
Pen G + Gent
OR
Amp + Gent
L. monocytogenes:
Alternatives ?
TMP-SMX
[Linezolid]
L. monocytogenes:
Duration of therapy ?
> 21 days
H. influenzae:
Amp-S
1st line ?
Amp
H. influenzae:
Amp-S
Alternatives ?
Cipro
[Chloram]
H. influenzae:
Amp-R, non-beta lactamase
1st line ?
Cefotax / Ceftriax (bc they have increased GN coverage to cover H. flu)
H. influenzae:
Amp-R, non-beta lactamase
Alternatives ?
Cipro
[Chloram]
H. influenzae:
Amp-R, B-lactamase
1st line ?
Mero
H. influenzae:
Amp-R, B-lactamase
Alternatives ?
Cipro
[Chloram]
H. influenzae:
Duration of therapy ?
7 - 10 days
S. agalactiae:
1st line ?
Pen G (+ Gent x 5 days)
OR
Amp (+ Gent x 5 days)
S. agalactiae:
Alternatives ?
Vanco
[Chloram]
S. agalactiae:
Duration of therapy ?
14-21 days
Streptococcal meningitis:
Invasive disease in _____
Manitoba
Streptococcal meningitis:
Declining incidence as a result of ?
conjugate vaccination
Streptococcal meningitis:
Increasing incidence of ?
non-included serotypes
What is the role of adjunctive dexamethasone therapy ?
- RR mortality = 0.48
- Post-hoc analysis showed benefit in pneumococcal disease only
Who is adjunctive dexamethasone therapy recommended for?
-immunocompetent adults with suspected or proven pneumococcal meningitis, and infants or children with H. influenzae (or pneumococcal ?) meningitis based on prior data
What is the dose for Dexamethasone ?
0.15 mg/kg q6h x 2-4 days initiated 10-20 min before or with 1st antibiotic dose
Dexamethasone therapy:
Continue only if ?
GPDC on gram stain or S. pneumonia culture
Dexamethasone therapy:
There are concerns regarding reducing antibiotic penetration of which drugs ?
Vancomycin and possibly Rifampin
If they already had a dose of antibiotics, do you still give Dex ?
No - it is ineffective now
What is the point of giving Dex ?
- steroids decrease inflammation
- reduce amount of hearing issues after meningitis (especially in kids)
Meningitis Monitoring:
When should fever resolve ?
within 24-48 hours
Meningitis Monitoring:
When should neck stiffness resolve ?
over 48 - 72 hours
Meningitis Monitoring:
When should CSF show a culture negative ?
within 24 hours
Meningitis Monitoring:
When should glucose be normal ?
3 days
Meningitis Monitoring:
When should
When should protein be normal ?
7 - 10 days
Meningitis Monitoring:
When should RASH resolve ?
over 7 days
Chemoprophylaxis for who ?
For those whose close contacts have had meningococcal infections within the past 60 days
What is the treatment for Chemoprophylaxis for Meningitis ?
just list them
- Cipro
- Rifampin
- Ceftriaxone
Dose of Cipro for Chemoprophylaxis
Adults:
500 mg PO x 1 dose
Children:
10 mg/kg PO x 1 dose (max 500 mg)
Dose of Rifampin for Chemoprophylaxis
Adults:
600 mg PO q12h x 4 doses
Children 3 months - 12 years:
10mg/kg PO q12h x 4 doses
Dose of Ceftriaxone for Chemophrophylaxis
Adults:
250 mg IM x 1 dose
Children under 12:
125 mg IM x 1 dose
