Dr. Loo -- CNS Infections Flashcards
1
Q
Define meningitis
A
Inflammatory disease of the leptomeninges, the tissues surrounding the brain and the spinal cord
2
Q
5 categories of meningitis
A
- Bacterial
- Viral
- Fungal
- Mycobacteria
- Parasitic
3
Q
2 sub-categories of bacterial meningitis
A
- Community-acquired
- Healthcare-associated Post neurosurgical
4
Q
4 pathogens associated with community-acquired meningitis in infants less than 1 month old
A
- *Streptococcus agalactiae *(Group B)
- E. coli
- Listeria monocytogenes
- *Klebsielle *spp.
5
Q
5 pathogens associated with community-acquired meningitis from ages 1 - 23 months
A
- Strep. pneumoniae
- N. meningitidis
- S. agalactiae
- H. influenzae
- E. coli
6
Q
2 pathogens associated with community-acquired meningitis from 2 - 50 years old
A
- N. meningitidis
- S. pneumoniae
7
Q
4 pathogens associated with community-acquired meningitis >50 years of age
A
- S. pneumoniae
- N. meningitidis
- L. monocytogenes
- Aerobic Gram negative bacilli
8
Q
2 most common pathogens for meningitis
A
- Streptococcus pneumoniae
- Neisseria meningitidis
9
Q
Most common serogroup of N. meningitidis
A
Serogroup B (out of 12)
10
Q
Age group with highest rates of meningitis
A
<20 years old
11
Q
3 risk factors for *N. meningitidis *meningitis
A
- Complement deficiencies
- Functional or anatomic asplenia
- Household exposure to an infected person
12
Q
Bacterial meningitis due to *N. meningitidis *transmission
A
Droplets; respiratory secretions
13
Q
Bacterial meningitis due to *N. meningitidis *carriage
A
Nasal
14
Q
Reason for decreased incidence of meningitis due to *S. pneumoniae * in 2005 and 2011
A
Introduction of conjugated pneumococcal vaccine PCV7 (2005) and PCV13 (2011)
15
Q
*N. meningitidis *meningitis mortality
A
10 - 20%
16
Q
*S. pneumoniae *meningitis mortality
A
20 - 25%
17
Q
9 risk factors for *S. pneumoniae *meningitis
A
- Splenectomy or asplenic states
- Mulitple myeloma
- Hypogammaglobulinemia
- Alcoholism, chronic liver
- Renal disease
- Malignancy
- DM
- Children with cochlear implants with positioners beyond 24 months after implantation
- CSF leak
18
Q
Reason that meningitis due to *H. influenzae *is rare
A
Vaccination since 1998
19
Q
Group affected by H. influenzae meningitis (2)
A
- Unimmunized children
- Partially immunized children
20
Q
*H. influenzae *meningitis transmission
A
Droplet
21
Q
Acquisition of menigitis due to Listeria monocytogenes
A
Contaminated foods
- Coleslaw
- Raw vegetables
- Milk and cheese
- Processed meats
22
Q
Mortality of *Listeria monocytogenes *meningitis
A
15 - 30%
23
Q
Most common cause of bacterial meningitis in neonates
A
*Streptococcus agalactiae *(GBS)
24
Q
Mortality of GBS meningitis
A
7 - 27%
25
Method of transmission of GBS meningitis
Through birth canal
26
3 pathogens of healthcare-associated bacterial meningitis
* Aerobic gram negative bacilli including *P. aeruginosa*
* *Staphylococcus*
* Coagulase negative
* *S. aureus*
* *Propionibacterium acnes*
27
Virus responsible for 85 - 95% of viral meningitis
Enterovirus
28
Enterovirus transmission
Person-person
29
Enterovirus seasonality
Summer and fall
30
2 less common causes of viral meningitis
* Arboviruses -- mosquitoes or ticks (can also cause encephalitis)
* Herpes simplex
31
6 non-specific clinical manifestations of viral meningitis in infants
* Fever
* Poor feeding
* Vomiting
* Lethargy
* Irritability
* Bulging Fontanelle
32
4 clinical manifestations of viral meningitis in older children
* Vomiting
* Photophobia
* Headache
* Neck stiffness
33
10 clinical manifestations of viral meningitis in adults
* Fever
* Headache
* Meningismus
* Altered mental status and sensorium
* Vomtiing
* Seizures
* Papilledema
* Neck stiffness
* Brudzinski's sign
* Kernig's sign
34
Define Brudzinski's sign
* "Nape of the neck sign"
* Passive flexion of the neck results in flexion of the hips and knees
35
Define Kernig's sign
* Patient supine with thigh flexed on the abdomen and the knee flexed
* Leg is passively extended
* In the presence of meningeal inflammation, patient resists leg extension
36
2 things rash may suggest
* *N. meningitidis* (75%)
* Enterovirus meningitis
37
What might cranial nerve findings suggest?
*L. monocytogenes*
38
7 ways to manage meningitis
* ABCs
* Level of consciousness; possible intubation
* Circulatory -- BP
* Blood cultures
* Lumbar puncture
* Empiric antibiotics
* CT scan in certain cases
39
5 situations where you should do CT scan in even of meningitis
* Immunocompromised
* Focal neurologic signs
* Seizure
* Papilledema
* Decreased level of consciousness
40
Difference between bacterial vs. viral meningitis: Cell count (cells/mm3)
* Bacterial = 1000 - 5000
* Viral = 100 - 1000
41
Difference between bacterial vs. viral meningitis: protein lab findings
* Bacterial = 1.0 - 5.0
* Viral = 1.0 (moderate increase)
42
Difference between bacterial vs. viral meningitis: glucose
Bacterial = low
Viral = normal
43
Difference between bacterial vs. viral meningitis: gram stain vs. blood culture
Bacterial = positive 60 - 90%
Viral = pasitive 10 - 90%
44
Appearance of *N. meningitis*
Gram negative cocci in pairs
45
Appearance of H. influenzae
Gram negative coccobacilli
46
Appearance of *s. pnuemoniae *and GBS
Gram positive coccin in pairs
47
Appearance of listeria monocytogenes
Gram positive rods
48
Empiric antibiotics for neonatal bacterial meningitis patients
Ampicillin IV + Cefotaxime IV
49
Empiric antibiotics for infants 1 - 3 months old with bacterial meningitis
Ampicilliln IV + Vancomycin IV + Cefotaxime or Ceftriaxone IV
50
EMpiric antibiotics for bacterial meningitis patients that are pediatrics and adult up to 50 years old
Cefotaxime or Ceftriaxone IV + Vancomycin IV
51
Empiric antibiotics for adult (\>50 years) and immunocompromised patients with bacterial meningitis
Ampicillin IV + Vancomycin IV + Cefotaxime or Ceftriaxone IV
52
Antibiotic regimen for empiric therapy of healthcare associated bacterial meningitis (2)
Vancomycin and Ceftazidime
OR
Vancomycin and Meropenem
53
Antibiotics for *S. pneumonia *bacterial meningitis and duration
* Penicillins
* Cefotaxime or Ceftriaxone IV
10 - 14 days
54
Antibiotics for *N. meningitidis* bacterial meningitis and duration
Penicillins IV or Cefotaxime/Ceftriaxone IV
5 - 7 days
55
Antibiotics for *H. influenzae* type B bacterial meningitis and duration
Cefotaxime or Ceftriaxone IV
10 - 14 days
56
Antibiotics for GBS bacterial meningitis and duration
Beta lactam IV + aminoglycoside IV
10 - 14 days
57
Antibiotics for *L. monocytogenes* bacterial meningitis and duration
Beta lactam IV + aminoglycoside IV
21 days
58
2 causes of meningitis where IV dexamethsone is recommended as an adjunct
* *H. influenzae* at any age
* *S. pneumoniae *in adults
59
Rationale for using adjunctive steriods in the treatment of bacterial meningitis
Prevent neurological damage (esp. to hearing) due to an inflammatory and cytokine influx after antiobitics cause lysis of bacteria and release of pro-inflammatory factor into the closed brain space
60
3 prophylactic antibiotics for *N. meningitidis *and *H. influenzae* meningitis
* Rifampin
* Ceftriaxone
* Ciprofloxacin
61
Define encephalitis
Inflammatory process of the brain parenchyma
62
7 associated clinical findings of encephalitis
Findings of **brain dysfunction**:
* Altered mental status (range = subtle deficits to complete unresponsiveness)
* Motor and sensory deficits
* Altered behavior and personality changes
* Speech or movement disorders
* Meningeal irritation (i.e. nuchal rigidity usually absent)
* Seizures
* Hemiparesis, craniael nerve palsies
NOTE: Meningitis = usually NORMAL brain function
63
2 most frequent age groups affected by encephalitis
* Infants \<1 year
* Elderly \> 65 years
64
3 possible etiologies of encephalitis
* Usually infectious
* Predominantly viral
* Non-infectious unusual
* Autoimmune disorders (i.e. collagen vascular diseases)
* Paraneoplastic syndromes
65
Virus that can cause encephalitis from animal bites
Rabies
66
Virus that can cause encephalitis from bats or pigs
Nipah virus
67
Virus that can cause encephalitis from rodents
Lymphocytic choriomeningitis
68
Seasonality of encephalitis
Summer (mosquitoes)
69
5 diagnostic lab tools for encephalitis
* CSF analysis
* Gram stain and culture
* Mycobacteria, funal, viral culture
* PCR
* Serology
* West Nile serology
70
5 viruses for which PCR could be used to diagnose encephalitis
* HSV
* Enterovirus
* Immunocompromised:
* VZV
* EBV
* CMV
71
4 findings from CSF analysis for encephalitis
* Increased WBC (but usually \<250/mm3)
* Predomniance of lymphocytes
* Increased protein (usually \<1.5 g/l)
* Normal glucose usually
* Decreased in HSV and mumps
* Red cells suggest necotizing encephalitides (i.e. HSV)
72
3 imaging techniques to diagnose encephalitis
* MRI
* CT
* EEG
73
MRI or CT scan findings that suggests HSV as cause of encephalitis
Temporal lobe involvement
74
MRI or CT scan finding to suggest arbovirus as cause of encephalitis
Thalamus or basal ganglia
75
EEG finding for encephalitis that suggests HSV as cause
Focality in the temporal lobe
76
Therapy for HSV encephalitis
Acyclovir 10 mg/kg IV q 8h (adjust for creatinine clearance)
77
Potential sequelae of encephalitis (4)
* Difficulty concentrating
* Behavioral
* Speech
* Memory
78
Bacterial meningitis triad
* Fever
* Headache
* Nuchal rigidity
NOTE: Not all patients have
