Meningitis Flashcards
(110 cards)
1
Q
Bacterial meningitis causes how many cases a year?
A
4-6 cases per 100,000 people
2
Q
80% of meningitis is caused by which bacteria?
A
streptococcus pneumoniae and neisseria meningits
3
Q
If a patient has a gram-negative bacillary meningitis, they have a 60 % chance of developing what complications?
A
irreversible complications
4
Q
What are examples of gram-negative bacillary meningitis?
A
pseudomonas aeruginosa or enterobacter species like E.coli
5
Q
What different pathogen types can cause meningitis?
A
bacteria, viral, fungal, parasitic, and mycobacterium (tuberculosis)
6
Q
What are bacteria pathogens that cause meningitis?
A
streptococcus pneumoniae, neisseria meningitidis, haemophilus influenzae, and monocytogenes
7
Q
What are viral pathogens that can cause meningitis?
A
enterovirus, arbovirus, and herpes
8
Q
What are parasitic pathogens that can cause meningitis?
A
naeglaria species and acanthamoeba species
9
Q
What are fungal pathogens that can cause meningitis?
A
cyroticiccus neoformans
10
Q
What is the most common causative agent of meningitis in infants younger then 2 years of age?
A
Group B streptococcus (GBS)
11
Q
Why is GBS the most common in infants 2 years of age?
A
GBS are normal flora of the birth canal and can be transmitted to infants during childbirth
12
Q
What is the most common causative agent of meningitis in children 2-10 years of age?
A
streptococcus pneumoniae
13
Q
What is the most common cause of meningitis in adolescents 11-17 years of age as well as young adults 18-34?
A
neisseria meningitidis
14
Q
What is the most common causative agent of meningitis in adults 35 and older?
A
streptococcus pneumoniae
15
Q
What are the 3 layers of the meninges?
A
dura mater, arachnoid, and pia matter
16
Q
What is the most external layer that lays against the skull bone?
A
dura mater
17
Q
What is the most internal layer that cover the brain?
A
pia mater
18
Q
When you give an antibiotic for meningitis, what must it be able to penetrate?
A
it must penetrate into the Cerebrospinal fluid to reach the meninges
19
Q
What is the different pathophysiology of meningitis?
A
mucosal colonization, intravascular survival, meningeal invasion, subarachnoid space invasion and blood brain barrier disruption?
20
Q
What is the most common cause of meningitis?
A
mucosal colonization
21
Q
To cause meningitis, a pathogen must be able to ?
A
Pathogens must have fimbriae to be able to attach to mucosal layers and “climb” into the meninges
22
Q
Which pathogens possess fimbriae?
A
H. influenzae and N. meningitidis
23
Q
Which pathogen is a polysaccharide capsule?
A
S. pneumoniae
24
Q
What is intravascular survival?
A
It can occur from mucosal colonization and it is where bacterial can translocate from one region to the blood and CSF
25
When would you see meningeal invasion, subarachnoid space invasion or BBB disruption?
It occurs with more invasive bacteria due to inflammation
26
What happens when bacteria invade the meninges?
inflammation occurs which leads to the disruption of the BBB
27
The cells that comprise the BBB have very tight junctions between them making them?
the cells make it nearly impermeable to almost everything
28
If just one bacterium crosses the BBB, it can cause?
inflammation or disruption of the BBB, which allows more bacteria to cross over and infect the meninges resulting in severe disease
29
What are clinical presentations of meningitis in adults?
```
Headache
Fever
Stiff Neck (nuchal rigidity)
Photophobia
Altered mental status
Obtundation (altered consciousness)
Seizures
Vomiting
```
30
What are clinical presentations of meningitis in infants?
```
Irritability
Altered sleep
Vomiting
High-pitched cry
Decreased oral intake
```
31
What are clinical presentations of meningitis in children?
Lethargy
Confusion
Somnolence
32
What are clinical signs of meningitis?
Brudzinski's neck sign
Kernig's sign
Babinski sign
33
What is the Brudsinski's neck sign?
- Flexion of the neck causes hip and knee flexion (positive or negative)
- Positive result is a potential sign of problems with meninges
34
What is Kernig's sign?
-Inability to straighten the leg (knee always stays flexed) when hip is flexed to 90 degrees
35
What is the Babinski sign?
- A pen is strobed on either top or bottom of foot, and toes should go down
- If toes curl upward, it is a positive sign
36
How much CSF should be in infants, children, and adults?
- Infants, 50 mL
- Children, 100 mL
- Adults, 150 mL
37
Cerebrospinal fluid is obtained through what?
Spinal Tap (or Lumbar Puncture)
38
When is a lumbar puncture indicated?
It is indicated for all patients who are suspected of having meningitis to determine if they have meningitis and if the causative agent is bacterial, viral, fungal, or parasite
39
What is the appearance of CSF?
- Normal clear
- Sterile
- 50-60% serum glucose
- pH 7.4
- Less than 5 WBC/mm3
40
What is CSP levels used to diagnose bacterial meningitis?
- WBC 1000-5000
- Neutrophil >80%
- Protein 100-500, bacteria eat sugar and spit out proteins
- Glucose <40 CSF/Serum ratio <0.4
41
What is important to not in diabetic patients in regards to glucose and protein levels?
Elevated glucose levels should NOT rule out a diagnosis of bacterial meningitis especially if protein levels are elevated
42
What are diagnostic methods of meningitis?
- CSF evaluation
- Enzyme immunoassay (EIA)
- Polymerase Chain Reaction (PCR)
43
How is CSF used as a diagnostic method?
Following analysis, a CSF will be sent for a gram stain
44
How is enzyme immunoassay used as a diagnostic method?
It is used for unusual pathogens that may not grow in culture
45
How is PCR used as a diagnostic method?
It is used to look for viruses, mycobacteria, and fungi
46
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A 23 yo UNM student present with severe headache, nausea, nuchal rigidity, altered mental status and high fever for the past 24 hours. What pathogens should be empirically covered in this patient suspected to have meningitis?
A. Streptococcus pneumonia
B. Listeria monocytogenes
C. Neisseria meningitis
D. A and C
E. A, B, and C
```
D. A and C
47
What is empiric therapy for meningitis?
CVD - ceftriaxone, vancomycin, and dexamethasone
48
What are the goals of therapy when treating meningitis?
- Eradicate infection
- Ameliorate signs and symptoms of infection
- Prevent complications
49
What is included in the management of meningitis?
- Empiric antibiotics
- Anti-inflammatory agents
- Fluids
- Electrolytes
- Antipyretics
- Analgesia
50
What are factors that improve antibiotic penetration?
- Low molecular weight
- Non-ionized
- Low protein bound percentage
- Lipophilic
51
Will certain antibiotics like Cefazolin penetrate the BBB?
Cefazolin has activity against s. pneumoniae but it does not penetrate the BBB so should not be used against meningitis
52
Will an aminoglycoside penetrate the BBB?
No, aminoglycosides are hydrophilic
53
How should a patient be treated if they are suspected of meningitis adn factors to consider?
- Empiric therapy should be initiated (CVD) until pathogen is identified
- Factors such as age of patient, allergies and concurrent medical conditions need to be considered
54
How soon is empiric therapy of meningitis completed and how long should it be continued?
- It should be initiated within 30 minutes of presentation even if LP not obtained
- Should be continued for 48-72 hours until diagnosis can be ruled out
55
What should you do when the infecting organism is identified?
Tailor therapy to infecting organism
56
What is the empiric regimen of meningitis for adults?
Ceftriaxone 2 g IV Q12H (or Cefotaxime 2 g IV Q6H) + Vancomycin 1 g IV Q 12H
57
What is the difference between Ceftriaxone and Cefotaxime?
- The only difference is the dosing frequency (q12H vs q6H)
| - Ceftriaxone is preferred as it dosed less frequent
58
When is vancomycin used in empiric therapy of adults?
It is used when incidence of penicillin-resistant S. pneumoniae is >5%
59
What is the empiric regimen of meningitis in neonates, elderly and alcoholics?
Ceftriaxone 2g IV q 12H (or Cefotaxime 2g IV q 6H) + Vancomycin 1 g IV q 12H + Ampicillin 2 g IV q 4H (adults)
60
Why is Ampicillin added for empiric regimen of neonates, elderly, and alcoholics?
They have an increased incidence of listeria monocytogenes
61
What is the anti-inflammatory agent added for treatment of meningitis?
Dexamethasone
62
What is the MOA of dexamethasone?
inhibits the production of pro-inflammatory cytokines (TNF, IL-1)
63
What are 2 things to keep in mind about dexamethasone?
- Improves CSF parameters (bacterial meningitis)
| - Needs to be administered before antibiotics
64
Why does dexamethasone need to be administered before antibiotics?
If you use Ceftriaxone to kill S. pneumoniae, toxins will be releases that will trigger more inflammation
65
Precautions of dexamethasone
- Concern of increased GI bleeding
| - Concern of decreased antibiotic penetration
66
What is adult and pediatric dosing of dexamethasone?
- Peds Dex 0.4 mg/kg IV Q12H for 2 days
| - Adults Dex 10 mg IV Q6H for 4 days
67
Benefits of dexamethasone
- May decrease hearing loss secondary to meningitis in children
- May reduce mortality from S. pneumoniae meningitis by as much as 20%
68
When should dexamethasone be started and discontinued?
Dexamethasone should be started empirically for all cases suspected of meningitis, but if bacteria are identified as N. meningitidis, dex should be discontinued
69
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A 23 yo UNM student present with severe headache, nausea, nuchal rigidity, altered mental status and high fever for the past 24 hours. What would be an appropriate empiric regimen for this patient suspected to have meningitis?
A. Vancomycin LD then 1 g IV q8h
B. Dexamethasone 10 mg IV q6h
C. Ceftriaxone 2 g IV q24h
D. A and C
E. A, B, and C
```
E. A, B, and C
70
Evaluation of response? (5)
- Signs and symptoms q 4H
- Vital signs and cerebral dysfunction q 4H for 72 hours
- CSF for re-culture, PCR is not responding
- Identification and susceptibility testing usually takes 72H
- Individualize therapy based on results
71
Description of Neisseria Meningitidis
gram-negative diplococci
72
When is N. meningitidis seen?
- Children and young adults (college bug)
| - More common in winter and spring months
73
Clinical features of N. meningitidis?
- Incubation 3-4 days (2-10 days)
| - fever, arthritis, pericarditis
74
Clinical presentation of N. meningitidis?
behavioral changes, seizures, coma
75
Treatment of N. meninigitidis for meninigitis? (PCN susceptable)
- Penicillin G 24 mU/day divided q 4H in adults
- Peds PCN 0.3mU/kg/day divided q 4H
- D/C Ceftriaxone, Vancomycin and Dexamethasone
76
Treatment of N. meninigitidis for meninigitis? (PCN resistant)
- Ceftriaxone 2 g IV Q12H in adults
- Peds Ceftriaxone 80-100 mg/kg/day
- OR Cefotaxime 2 g IV q4-6H in adults and PEDS Cefotaxime 225-300 mg/kg/days
- D/C Vanco and Dex
77
Duration of treatment of N. meningitidis?
7 days
78
When is prophylaxis of contacts of N. meningitidis recommended?
Recommended for close contacts defined as household contacts, daycare members (exposed for at least 4 hours in the week prior to illness), and anyone directly exposed to the patient's oral secretions (kissing, mouth-to-mouth resuscitation, endotracheal management)
79
When should prophylaxis of N. menigitidis be started?
- Should be administered ASAP (ideally 24 h) but up to 14 days after contact
- Administration 12 days post-contact not useful
80
Prophylaxis regimen of N. meninigitidis?
- Ceftriaxone 250 mg IM X 1 (<15 yoa 125 mg IM x 1)
- Alt: Rifampin 600 mg po q12H x 4 doses (child 1 month to 12 yoa Rifampin 10 mg/kg po q12H x 4 doses OR Child <1 mo Rifampin 5 mg/kg po q12H x 4 doses)
81
If patient has received Meningococcal vaccine, do they receive prophylaxis?
They will NOT need prophylaxis
82
Description of streptococcus pneumoniae?
gram-positive cocci in pairs
83
What is the most common cause of meningitis in adults and also seen commonly in children?
S. pneumoniae
84
S. pneumoniae is commonly seen in patients with predisposition with?
Pneumonia, endocarditis, splenectomy, head trauma, alcoholism, sickle cell anemia, and bone marrow transplant
85
Treatment of S. pneumoniae if PCN susceptible?
- Continue dex x 4 days total
- Ceftriaxone adults 2 g IV Q12H OR Peds 100 mg/kg/day divided Q12-24H (OR Cefotaxime adults 2 g IV Q4-6H OR Peds 200 mg/kg/day divided Q6H
- May switch to PCN but don't have to
86
Treatment of S. pneumoniae if Ceftriaxone/Cefotaxime resistant?
- Continue dex x 4 days total
- Ceftriaxone adults 2 g IV Q12H OR Peds 100 mg/kg/day divided Q12-24H (OR Cefotaxime adults 2 g IV Q4-6H OR Peds 200 mg/kg/day divided Q6H
- Add Vancomycin AND keep Ceftriaxone/Cefotaxime
87
What is the duration of treatment of S. pneumonia for meningitis?
10-14 days
88
Description of Haemophilis influenzae
gram-negative bacili (coccobacili)
89
Hallmarks of HiB meningitis?
- Fever, decreased mental status and stiff neck
| - May have morbiliform or petechial rash
90
Treatment of H. influenzae in beta-lactamase negative isolates?
- Adults Ampicillin 2 g IV q4H
- Peds Ampicillin 200 mg/kg/day divided Q6H
- Continue Ceftriaxone and Dexamethasone for 4 days
- D/C Vancomycin
91
Treatment of H. influenzae in beta-lactamase positve isolates?
-Adults Ceftriaxone 2 g IV q 12H
-Peds Ceftriaxone 100 mg/kg/day divided Q12-24H
(OR Cefotaxime Adults 2 g IV q4-6h and Peds 100 mg/kg/day divided q6h)
92
What is the duration of therapy for H. influenzae meningitis?
10 days
93
When do you initiate prophylaxis for H. influenzae?
Close contacts such as household members, day care attendees, nursing home residents, crowded confined populations (>4 hrs/day of contact)
94
What is the prophylaxis treatment for H. influenzae?
- Adults Rifampin 600 mg po qd x 4 days
| - Peds 1 mo-12 yoa 20 mg/kg/day qd x 4 days
95
When would not initiate prophylaxis?
Individuals who are fully vaccinated (>2 yoa) would not benefit from prophylaxis
96
Description of listeria monocytogenes?
gram positive bacilli or coccobacilli
97
Who does listeria monocytogenes primarily effect and when?
- Neonates, immunocompromised adults and elderly
| - Peaks in summer and fall
98
Where does listeria monocytpgenes colonize and penetrate?
colonizes GI tract then penetrates gut lumen
99
What is the treatment of listeria monocytogenes?
- Adults Ampicillin 2 g IV q4H PLUS ADD gentamicin 5-7 mg/kg/day x 10 days
- Peds Ampicillin 300 mg/kg/day divided Q6H
- D/C Ceftriaxone/Cefotaxime, Vancomycin and Dexamethasone
100
What is treatment of listeria monocytogenes with a PCN allergy?
-TMP/SMX (Bactrim) 10-20 mg/kg/day
101
What is the duration of therapy for listeria monocytogenes meningitis?
21 days - longest drug regimen for meningitis
102
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CSF cultures obtained on admission on the 23 yo with meningitis are positive for Neisseria meningitidis 48 hours after initiating treatment. What would be the best therapeutic approach at this time?
A. D/C Vanco
B. D/C Ceftriaxone
C. D/C Dexamethasone
D. A and C
E. A, B, and C. Start PCN
```
D or E would be acceptable
103
A 19-year-old Caucasian male reports symptoms of Photophobia, Fever,
Headache, Vomiting, and Neck Stiffness for the past 2 days. A Lumbar Puncture (LP) is performed and reveals cloudy CSF, 1,000 WBCs (predominantly Neutrophils), Glucose of 45 mg / dL, and protein of 623 mg / dL. A Gram Stain reveals Gram-Negative diplococci. What is the most likely pathogen and recommended empiric treatment strategy?
A. Neisseria meningiditis, Dexamethasone and
Ceftriaxone
B. Haemophilus influenzae, Dexamethasone and
Ampicillin
C. Neisseria meningiditis, Dexamethasone, Ceftriaxone,
Vancomycin
D. Haemophilus influenzae, Dexamethasone,
Ceftriaxone, Vancomycin
E. Streptococcus pneumoniae, Dexamethasone and
Levofloxacin
C. Neisseria meningiditis, Dexamethasone, Ceftriaxone,
| Vancomycin
104
A 35-year-old male presents with a 2-day history of Cough, Headache
(HA), Nausea, Fever, and Photophobia. Upon examination, he is noted to have Nuchal Rigidity. A Lumbar Puncture (LP) is performed. What empiric antibiotics should this patient be initiated on?
- Ceftriaxone, Vancomycin and Dexamethasone
| - Not neonate, elderly or suspected alcoholic so no Ampicillin needed for listeria monocytogenes
105
A 35-year-old male presents with a 2-day history of Cough, Headache
(HA), Nausea, Fever, and Photophobia. Upon examination, he is noted to have Nuchal Rigidity. CSF: Cloudy; Glucose – 58 mg / dl, WBC – 97, 86% Neutrophils, 10%
Lymphocytes, and 3% Eosinophils, Protein 320, Gram-Stain Negative
CSF Culture: Pending; the patient is admitted to the general medicine ward. A Lumbar Puncture (LP) is performed. What organism do you suspect?
Elevated proteins in the CSF indicate Bacterial Meningitis, so the
organisms could be N. meningitidis, S. pneumoniae, H. influenzae, and L.
monocytogenes
106
A 35-year-old male presents with a 2-day history of Cough, Headache
(HA), Nausea, Fever, and Photophobia. Upon examination, he is noted to have Nuchal Rigidity. CSF: Cloudy; Glucose – 58 mg / dl, WBC – 97, 86% Neutrophils, 10%
Lymphocytes, and 3% Eosinophils, Protein 320, Gram-Stain Negative
CSF Culture: Pending; the patient is admitted to the general medicine ward. A Lumbar Puncture (LP) is performed
Follow-Up Details – The culture is now positive for Streptococcus pneumoniae (Pen-
Susceptible). The patient is afebrile and has had reduction of his Headache, Nausea, and
Fever. Is a modification in his regimen necessary? If so, what would you change?
Yes; we can keep them on Ceftriaxone and Dexamethasone, but we should discontinue Vancomycin. Alternatively, given that the S. pneumoniae is Penicillin-Susceptible, we could start the patient on Penicillin
107
A 35-year-old male presents with a 2-day history of Cough, Headache
(HA), Nausea, Fever, and Photophobia. Upon examination, he is noted to have Nuchal Rigidity. CSF: Cloudy; Glucose – 58 mg / dl, WBC – 97, 86% Neutrophils, 10%
Lymphocytes, and 3% Eosinophils, Protein 320, Gram-Stain Negative
CSF Culture: Pending; the patient is admitted to the general medicine ward. A Lumbar Puncture (LP) is performed
Follow-Up Details – The culture is now positive for Streptococcus pneumoniae (Pen-
Susceptible). The patient is afebrile and has had reduction of his Headache, Nausea, and
Fever. Is chemoprophylaxis warranted for the nursing staff?
None since the likely underlying cause is Viral or Fungal
108
A 70 yo male is admitted to UNMH from his nursing home. The nursing home staff report a deterioration in his cognitive functioning over the past 48 hours. On presentation the patient is A&O x 1 (to person only). He has no focal neurological findings but has recently developed urinary incontinence.
An MRI is performed which demonstrates diffuse white matter changes consistent with aging and no focal findings
An LP is performed: CSF: WBC: 400 80%N15%L5%M
Protein: 100 Glucose: 55 Gram stain: negative
What are the most likely pathogens?
L. monocytogenes, S. pneumoniae, and N. meningitidis
109
A 70 yo male is admitted to UNMH from his nursing home. The nursing home staff report a deterioration in his cognitive functioning over the past 48 hours. On presentation the patient is A&O x 1 (to person only). He has no focal neurological findings but has recently developed urinary incontinence.
An MRI is performed which demonstrates diffuse white matter changes consistent with aging and no focal findings
An LP is performed: CSF: WBC: 400 80%N15%L5%M
Protein: 100 Glucose: 55 Gram stain: negative
What diagnostic tests should be ordered?
LP and culture of CSF
110
A 70 yo male is admitted to UNMH from his nursing home. The nursing home staff report a deterioration in his cognitive functioning over the past 48 hours. On presentation the patient is A&O x 1 (to person only). He has no focal neurological findings but has recently developed urinary incontinence.
An MRI is performed which demonstrates diffuse white matter changes consistent with aging and no focal findings
An LP is performed: CSF: WBC: 400 80%N15%L5%M
Protein: 100 Glucose: 55 Gram stain: negative
What antimicrobial regimen would you initiate?
Ceftriaxone, Vancomycin, Dexamethasone and Ampicillin
