Lecture 18: Nervous System Flashcards
True or False: There is NF in your Nervous System
False - there is not!
____: Inflammation of brain parenchyma
____: Inflammation of spinal cord
Encephalitis
Myelitis
____: Localized pyogenic infection within brain
Brain Abscess
___: Inflammation of the meninges resulting from an infection in subarachnoid space
Meningitis
Most common cause of meningitis?
Viruses
- Bacteria is less rare
True or False: Tetanus mimics some s+s of meningitis
True
True or False: Meningitis occurs more frequently than encephalitis
True
What’s the difference between Septic (Purulent) Meningitis vs. Aseptic?
Septic
- Can cultivate organism
- Bacterial meningitis
Aseptic
- Non-pyogenic
- UK cause
- Usually infectious (viral!)
True or False: Bacteria and Viruses often cause acute meningitis while microbes often cause Chronic Meningitis
True
True or False: The course of bacterial meningitis can be fulminant
True
___ is a major pre-disposing factor for acute bacterial meningitis
Age
What is the most common mechanism for acquiring meningitis?
A. 1 invasion of CNS s/p infection of blood
B. 2 invasion of CNS s/p infection of blood
B. 2 invasion of CNS s/p infection of blood
How does meningitis enter Sub-arachnoid space?
Sites of minimal resistance
What is effect of direct entry of meningitis?
Damage to CNS integrity
In the case of brain abscesses, there is contiguous spread along ___ channels or ___ infection
vascular; parameningeal
______: a system used by neurotoxins, allows for transport system to and from neuron’s cell
Retrograde axoplasmic flow
Three most common sx of acute bacterial meningitis in NON-neonates (adults)?
- Fever
- Meningismus
- photophobia
- stiff neck
- headache - Altered mental status
Three types of rashes that may be seen with meningitis?
Maculopapular
Vesicular
Pupuric
- S. pneumonia
- N. meningitis
- H. Influenza
True or False: In Infants, bulging of fontanel is a clinical manifestation of acute bacterial meningitis
True
- Also: fever, irritability, inactivity, poor feeding
A newborn/neonate has acute bacterial meningitis. Which three organisms may be the culprit?
- E. coli K1
- S. agalactiae (strep B)
- Listeria monocytogenes
An infant-child has acute bacterial meningitis. Which three organisms may be the culprit?
- Strep pneumo
- H. Influenza (Type B)
- Neisseria meningitis
Which organism may cause acute bacterial meningitis in all groups except newborns?
Streptococcus pneumoniae
S. pneumonia and Listeria monocytogenes may cause acute bacterial meningitis in…
A. Elderly
B. Kids/Teens/Adults
C. Infants
D. Newborns
A. Elderly
S. pneumonia and N. meningitidis can cause acute bacterial meningitis in…
A. Elderly
B. Kids/Teens/Adults
C. Infants
D. Newborns
B. Kids/Teens/Adults
N. meningitis is likely to cause acute bacterial meningitis in which two groups?
- infants and kids
- children/teens/adults
Listeria monocytogenes can cause acute bacterial meninigitis in which two patient populations?
Elderly and newborns
Tests to r/o meningitis?
What are the three vertically transmitted pathogens?
- Streptococcus agalctia
- E. coli K1
- Listeria monocytogenes
Where is Streptococcus agalctia found? Can it be transmitted to newborns?
Female genital and GI tract
Yes!
Streptococcus agalctia
- Gram + or -?
- Shape?
- Linear or chains?
Gram +
Cocci
Chains
- also known as: group B streptococci
How are beta-hemolytic streptococci classfied?
Carbohydrate in cell wall
- Lancefield classification
Most common pathogen causing neonatal meningitis?
A. Streptococcus agalctia
B. E. coli K1
C. Listeria monocytogenes
A. Streptococcus agalctia
What is the main virulence factor of S. agalactiae?
A. Pili
B. Capsule
C. LT Toxin
B. Capsule
If you culture S. agalactiae, which three features would you expect to see?
B-hemolytic
Catalase (-)
Bacitracin resistant
___ is part of normal GI flora that spreads via vertical transmission. Its main virulence factor is: capsule.
___ is part of normal GI flora that spreads via vertical transmission. Its main virulence factor is: capsule
A. Streptococcus agalctia
B. E. coli K1
C. Listeria monocytogenes
B. E. coli K1
K1= capsule serotype
E. coli K1
- Gram + or -?
- Shape?
Gram - Bacilli
How can you detect K1 antigen of E. coli?
CSF
How is listeria transmitted? to who?
- How: contaminated foods
- Who: adults
Common foods associated with Listeria monocytogenes infections?
- Unpasteurized milk
- Undercooked meat
- Raw veggies
True or False: Patients who are immune-competent may only have mild or asymptomatic with Listeria infection
True
What can occur if a pregnant mother has listeria?
- Febrile
- Could pass to baby, leading to menigitis
True or False: IC and elderly are also at risk for meningitis w/Listeria
True
Listeria….
- Gram +/-
- Infects…
-Facultative extra or intracellular?
Note: also known as coccobacilli
- Gram (+)
- Facultative intracellular pathogen
- Infects macrophages
Listeria monocytogenes survives within the phagosome. How does it escape?
Via production of: listeriolysin O (LLO)
- Type 2 Toxin (pore forming)
How does Listeria monocytogenes move cell to cell?
A. Actin Tail
B. Myosin Tail
C. Cytoplasmic Tail
A. Actin Tail
- similar to shigella
How are Listeria similar to Shigella?
1) Facultative intracellular pathogen - infects macrophages
2) Avoid phagolysosome
How can you culture L. monocytogenes?
Cold enrichment
Beta-hemolytic
- Motility (tumbling/umbrella)
True or False: In L. monocytogenes, LLO+PLC are used to escape phagosome
True
___ proteins mediate nucleation of actin tail at one end of bacteria in Listeria monocytogenes
ActA
Which three pathogens can be transmitted via: respiratory droplets?
S. pneumoniae
H. influenzae
N. meningitis
In infants/children, there is vaccine prevention for which three pathogens?
S. pneumoniae
H. influenzae
N. meningitis
Where is S. pneumo commonly found? Transmission?
- Upper respiratory
- Respiratory droplets
S. pneumo is most common agent of which condition?
A. Chronic viral meningitis
B. Acute bacterial meningitis
B. Acute bacterial meningitis
True or False: Streptococcus is gram (+) diplococci
True
True or False: S. pneumo uses capsule for virulence factor
True
Which two toxins does S. pneumo make that allows for tissue destruction?
- Pnuemolysin
- Phosphocholine (can enter RBC)
S. pneumoniae
H. influenzae
N. meningitis
What two things do they have in common?
Virulence factor = capsule
IgA Protease
If you cultured S. pneumo, what three features would you notice?
Alpha hemolytic (blood agar)
Catalase (-)
Optochin sensitive
How do you detect antigen of S. pneumoniae?
From CSF