Meningitis Flashcards
T or F: it is more difficult to get through the BBB than the BCSF barrier
TRUE
Antibiotic Characteristics that influence CSF/CNS Penetration:
Lipid Solubility:
- Lipid soluble drugs penetrate brain tissue more readily than hydrophilic drugs
Ionization:
- Only unionized drugs can diffuse
Protein Binding:
- Only free drug can penetrate
Molecular Weight:
- Agents with low molecular weight penetrate better
Degree of Meningeal Inflammation:
- Penetration of some drugs into CSF is enhanced with inflammation; decreased penetration as healing progresses
Therapeutic CSF Concentrations
With or Without Meningeal Inflammation
Acyclovir
TMP/SMX
Voriconazole
Fluconazole
Ganciclovir
Linezolid
Metronidazole
Fluoroquinolones
Therapeutic CSF
Concentrations WITH
Meningeal Inflammation
Penicillins
Some Cephalosporins
(3rd and 4th generation)
Aztreonam
Meropenem
Colistin
Vancomycin
Therapeutic CSF Concentrations NOT Achieved With or Without Meningeal Inflammation
Macrolides
Aminoglycosides
B-lactamase inhibitors
Some cephalosporins (1st and most 2nd generation)
Clindamycin
Tetracyclines (exception Doxycycline)
Echinocandins
Which of the following antibiotics does NOT achieve therapeutic concentrations in the CSF, even in the presence of inflamed meninges?
A. Cefazolin
B. Penicillin G
C. Ceftriaxone
D. Ertapenem
E. A and D
Cefazolin and Ertapenem
Which of the following is not a characteristic that effects CNS
penetration?
A. Excretion
B. Molecular weight
C. Protein binding
D. Ionization
Excretion
Bacterial Meningitis: Physical Signs
Symptoms
Fever, chills
Headache, backache, nuchal rigidity, mental status changes
Photophobia
Nausea/vomiting, anorexia, poor feeding habits (infants)
Petechiae or purpura (N. meningitidis)
Physical Signs:
- ___ and ___ sign
- bulging ___
- meningococcal ___
- kernig, brudzinski
- fontanel
- rash
CSF Interpretation: bacterial
WBC: > ___ - ___
differential: > ___ % neutrophils
protein: > ___
glucose: < ___ mg/dL
- 1000-5000
- 80%
- 150
- 50
Microbiology: Gram Stain of CSF typically positive, Culture and Susceptibility. Additional studies – Biofire PCR, latex agglutination, India Ink, Cryptococcal antigen, AFB PCR
Acute Bacterial Meningitis
Which of the following findings would be expected in the cerebrospinal fluid (CSF) analysis and culture of a patient with
suspected acute bacterial meningitis?
A. Low glucose concentration (< 50% of serum glucose concentration)
B. Low protein concentration (< 50 mg/dL)
C. A predominance of monocytes in the white blood cell count differential
D.Negative Gram stain and culture
E. Low white blood cell count (< 5 cells/mm3)
Low glucose concentration (< 50% of serum glucose concentration)
bacteria eating it all up
Empiric Antibiotics:
neonates:
- ___ + ___ or ___
- ___ + ___
infants, children, and adults: ___ + ___
older adults ( >50 yrs): ___ + ___ + ___
neonates
- amp + ceft or cefepime
- amp + aminoglycoside
infants, children, adults
- vanc, ceft
older adults
- vanc, ceft, amp
Role of Steroids:
Current AAP recommendations: consider steroids in children > 2 months of age with suspected meningitis
Useful in pneumococcal meningitis in adults → decrease mortality and ___ ___
Administer before or with 1st dose of the antibiotic
- Duration: 2-4 days
neurologic sequelae
Directed Therapy and Duration:
S. pneumonia:
- Pen S – PenG or Ampicillin
- Pen R – Vancomycin + Ceftriaxone
- 10 – 14 days
GroupB Strep:
- Ampicillin ± Gentamicin
- 14 – 21 days
S. aureus
- MSSA: Nafcillin
- MRSA: Vancomycin
- 14 – 21 days
L. monocytogene
- Ampicillin ± Gentamicin
- 21 days
N. meningitidis
- Penicillin or Ceftriaxone
- 7 days
H. influenzae
- βL(-) – Ampicillin
- βL(+) – Ceftriaxone
- 7 days
Gram-Negative
- Ceftriaxone or Cefepime
- 21 days
S. pneumonia:
- Pen S – PenG or ___
- Pen R – ___ + ___
- __ – __ days
GroupB Strep:
- ___ ± Gentamicin
- ___ - ___ days
S. aureus
- MSSA: ___
- MRSA: ___
- __ - __ days
L. monocytogene
- ___ ± Gentamicin
- __ days
N. meningitidis
- Penicillin or ___
- __ days
H. influenzae
- βL(-) – ___
- βL(+) – ___
- __ days
Gram-Negative
- ___ or Cefepime
- ___ days
A 58-year-old male is admitted for suspected bacterial meningitis (LP with low glucose, elevated bacteria and WBC).
He also has a PMH of COPD, CAD, HTN, HLD. What would be the best empiric treatment option?
A.Ceftriaxone + vancomycin
B.Ceftriaxone + vancomycin + dexamethasone
C.Ampicillin + ceftriaxone
D.Ampicillin + ceftriaxone + vancomycin
E.Ampicillin + ceftriaxone + vancomycin + dexamethasone
Ampicillin + ceftriaxone + vancomycin + dexamethasone
The same patient has a gram stain done which shows gram positive cocci in pairs and chains. What would be the best
course of action?
A. Continue ceftriaxone + vancomycin
B. Continue ceftriaxone + vancomycin + dexamethasone
C. Continue ampicillin + ceftriaxone + vancomycin + dexamethasone
D. Continue ceftriaxone + dexamethasone
E. Continue ampicillin
Continue ceftriaxone + vancomycin + dexamethasone
T or F: Dexamethasone has been shown to decrease mortality and unfavorable outcome in adults with bacterial meningitis due to any organism
FALSE
Only in meningitis due to Streptococcus pneumoniae
Fungal Meningitis
Cryptococcus ___
- Predominant pathogen (80% of human cases)
Cryptococcus gatti
Risk Factors:
- Advanced HIV (CD4 < ___ cells/mL)
- Non-HIV Immunosuppression:
Corticosteroid use
Organ transplant
Cirrhosis
Sarcoidosis
Lymphoma, hematologic malignancies
- neoformans
- 200
CSF Interpretation: fungal
WBC: ___ - __
differential: > ___ % lymphs
protein: ___ - ___
glucose: < __ - __
- 10-500
- 50%
- 40-150
- 30-70
fungal Treatment Overview:
3 phases: ___ , ___ , and ___
Control of CSF pressure
Addressing immune suppression
⎻ Induction
⎻ Consolidation
⎻ Maintenance
fungal Induction Phase:
Ampho B: 0.7-1 mg/kg/day (infused over 24 hours)
OR
Liposomal ampho B 3-4 mg/kg/day
PLUS ___ 25 mg/kg PO QID
Duration: ___ weeks
- Flucytosine
- 2 weeks
fungal consolidation phase
Non-HIV infected patient:
Preferred: ___ 400-800 mg PO or IV once daily
Duration: ___ weeks
Persons living with HIV:
- same
- Fluconazole
- 8 weeks
fungal Maintenance Phase:
Preferred:
___ 200 mg PO once daily
Duration:
Non-HIV infected patient: __ - __ months
Persons living with HIV:
⎻At least ___ months AND CD4 > ___ cells/mL AND suppression of viral load on ART
HIV/AIDS
ART should be initiated, but not until __ weeks after initiation of treatment for cryptococcal meningitis
- fluconazole
- 6-12 months
- 12 months, 200
- 5 weeks
A renal transplant patient is admitted with a 3 week history of headache, photophobia and fever. The LP demonstrates 80 WBC with 90% lymphs, and his serum and CSF cryptococcal antigen titers are positive. Which therapy would be most appropriate for this patient?
A. Liposomal ampho B 4 mg/kg IV daily
B. Conventional ampho B 1 mg/kg IV daily over 4 hours + flucytosine PO
C. Fluconazole 400mg IV QD
D. Conventional ampho B 1 mg/kg IV daily over 24 hours + Flucytosine PO
E. Caspofungin 50mg IV QD
Conventional ampho B 1 mg/kg IV daily over 24 hours + Flucytosine PO
infuse over 24 hrs
