Meningitis Flashcards
1
Q
Meningitis Epidemiology
A
- Most caused by S. pneumoniae and N. meningitidis
- Surviving a gram “-“ bacilli meningitis has a 60% risk of developing a complication
- Can also be fungal, viral, mycobacteria, or parasitic in nature
2
Q
Meningitis Pathophysiology
A
- Mucosal colonization: fimbriae and polysaccharide are pathogenicity factors
- Survive intravascularly
- Invade meningeal and subarachnoid space invasion
- Cause blood barrier disruption
3
Q
Meningitis Adult Presentation
A
- Headache
- Fever
- Stiff neck
- Photophobia
- Altered mental status
- Obtundation
- Seizures
- Vomiting
4
Q
Meningitis Infant Presentation
A
- Irritability
- Altered sleep
- Vomiting
- High-pitched cry
- Decreased oral intake
5
Q
Meningitis Children Presentation
A
- Lethargy
- Confusion
- Somnolence
6
Q
Meningitis Signs
A
- Bilateral
- Inability to straighten leg when hip flexed 90 degrees
- Flexion of the neck causes hip/knee flexion
- Babinski sign (absent)
7
Q
Cerebrospinal Fluid
A
- Flows unidirectionally and increases in volume with age
- Normally clear, 50-60% serum glucose, pH 7.4, and <5 WBCs/mm3
- Used to diagnose meningitis
8
Q
Cerebrospinal Fluid + Bacterial
A
- WBC: 1,000-5,000
- > =80% neutrophilic
- Protein: 100-500
- Glucose: =<40
- CSF/serum ratio =<0.4
9
Q
Cerebrospinal Fluid + Fungal
A
- WBC: 40-400
- Mainly lymphocytic
- Protein: 30-150
- Glucose: 30-70
10
Q
Cerebrospinal Fluid + Viral
A
- WBC: 5-500
- Mainly lymphocytic
- Protein: 40-150
- Glucose: 30-70
11
Q
Diagnostic Methods
A
- CSF Evaluation: gram stain and culture
- Enzyme immunoassay for bacteria
- PCR for viruses, mycobacteria, and fungi
12
Q
Goals of Therapy
A
- Eradicate infection
- Ameliorate signs and symptoms of infection
- Prevent complications
13
Q
Meningitis Management
A
- EMPIRIC ABX
- Anti-inflammatory agents
- Fluids
- Electrolytes
- Antipyretics
- Analgesia
14
Q
Abx Requirements for Penetration
A
- Low molecular weight
- Non-ionized
- Low protein bound
- Lipophilic
15
Q
Empiric Therapy
A
- Use until age, allergies, and concurrent medical conditions are identified
- Should be initiated within 30 minutes of presentation, even without LP
- Should be continued for 48-72 hours until diagnosis of meningitis is ruled out
- Tailor therapy to organism/sensitivities once identified
16
Q
Meningitis Empiric Treatment + Adults
A
-Ceftriaxone OR -Cefotaxime PLUS -Vanco
17
Q
Listeria Monocytogenes
A
- Gram “+” bacilli or coccobacilli
- Increased rates with neonates/ elderly, and alcoholics
- Colonizes GI tract and penetrates gut lumen
- Often misidentified
- Add ampicillin in adults
18
Q
Dexamethasone
A
- Anti-inflammatory
- Inhibits pro-inflammatory cytokine production
- Improves CSF parameters
- May help reduce hearing loss
- Give before abx
- Increased risk of GI bleed and decreased abx penetration
19
Q
Children + Dexamethasone
A
- Benefits shown in H.influenzae and MAYBE S. pneumoniae
- Start before or at the same time as abx
- Given for 2-4 days
20
Q
Adults + Dexamethasone
A
- Start before abx
- Give for 4 days
- Only continue if S. pneumoniae is the offending agent
21
Q
Evaluation of Response
A
- Signs and symptoms
- Vital signs and cerebral dysfunction q4h for 72 hours
- CSF reculture, PCR if not responsive
- Identification/susceptibility usually takes 72 hours
- Individualize therapy after receiving results
22
Q
Treating N. Meningitis
A
- PCN MIC < 0.06: PCN G q4h (different dosing based on age)
- PCN MIC >= 0.12: Ceftriaxone or cefotaxime
- Duration: 7 days
23
Q
Contact Prophylaxis
A
- Recommended for close contacts and anyone directly exposed to patient secretions
- Administer ASAP, if 14 days post-contact, probably not helpful
24
Q
Prophylaxis Regimens
A
- Ceftriaxone IM for 1 dose
- Amount varies depending on if over or under 15 y.o.
Alternatives
- Rifampin given over 4 doses
- Dosing amount varies based on age
25
Q
Streptococcus Pneumoniae
A
- Gram “+” diplococci
- Most common causer in adults
- Seen commonly in children too
26
Q
S. Pneumoniae + Risk Factors
A
- Pneumonia
- Endocarditis
- Splenectomy
- Head trauma
- Alcoholism
- Sickle cell disease
- Bone marrow transplant
27
Q
S. Pneumoniae Treatment
A
- Continue dexamethasone for 4 total days
- Cefotaxime or Ceftriaxone can be used (dosing based on age)
- If PCN susceptible MIC < 0.06: switch to PCN
- If ceftriaxone/cefotaxime MIC >=1: Vanco + 3rd gen cephalosporin
- Duration: 10-14 days
28
Q
Treatment of H. Influenzae
A
- 30-40% of isolates produce B-lactamase
- B-lactamase negative: Ampicillin
- B-lactamase positive: Cefotaxime or Ceftriaxone
- Duration: 10 days
29
Q
H. Influenzae Prophylaxis
A
- Close contacts, nursing home residents, crowded confined populations
- Rifampin over 4 doses
- Individuals fully vaccinated and over 2 y.o. may not benefit from prophylaxis
30
Q
Listeria Treatment
A
- Ampicillin PLUS AMG
- Alternative: Bactrim
- Duration: 21 days
