Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Block 9 - Neuro > Micro: Greenberg 2 > Flashcards

Micro: Greenberg 2 Flashcards

1
Q

What are the common agents of bacterial meningitis in infants, children and adults?

A

acquired via respiratory droplets

s. pneumoniae, n. meningitidis, H. flu type b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the common agents of bacterial meningitis in neonates?

A

acquired via maternal genital tract

s. agalactiae (group b strep), listeria, e. coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the microbiology of s. pneumoniae?

A

*gram+ cocci in pairs and short chains, alpha hemolytic

catalase negative, optochin sensitive, sensitive to bile lysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are risk factors for s. pneumo?

A

*cochlear implant or CSF leak

65, asplenic, alcoholic, HIV, diabetes, HIV, defects in humoral immunity, acquisition of new strain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are some virulence factors of s. pneumo?

A

pneumolysin

polysaccharide capsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the role of pneumolysin of s. pneumo?

A

pore-forming cytotoxin, lytic to host cells, impairs respiratory burst, induces inflammatory cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the role of the polysaccharide capsule of s. pneumo?

A

major virulence determinant
anti-phagocytic
negatively charged and inhibits: interxn of Fc stem and receptor, interxn of CR3 and iC3b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How is s. pneumo diagnosed?

A

culture from CSF or blood

rapid antigen detection test for CAP and meningitis (adults) - test both urine and CSF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the treatment of s. pneumo?

A

vanc + cephalosporin
high dose therapy, IV route
resistance rising, esp penicillin
vaccines are capsule based

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the microbiology of listeria monocytogenes?

A

gram+ non-spore forming rod, beta hemolytic
tumbling motility
grow in refrigerator, tolerate high salt concentrations, grow over wide range of pHs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the different diseases of l. monocytogenes?

A

diarrhea - most common, transient and undiagnosed, vomiting, epidemic gastroenteritis w fever
bacteremia
CNS inf - meningitis, meningoencephalitis, rhombencephalitis, cerebritis and brain abscess

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the characteristics of neonatal listeriosis?

A

transplacental transmission
early onset (24h-6days) after birth
loss of appetite, lethargy, jaundice, vomiting, respiratory distress, shock, hypothermia
results in: abortion, stillbirth, premature birth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the epidemiology of l. monocytogenes?

A

lots of pregnant women - mild symptoms

wild and domestic animals, birds, soil, crustaceans, fish, oysters, flies, ticks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How is l. monocytogenes acquired?

A

food borne, not person to person - deli meats!
immunocompromised individuals at risk
pregnancy is biggest risk factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the microbiology of N. meningitidis?

A

gram- diplo, optimal growth 35-37 degC
oxidase and catalase positive
require enriched CO2 for OPTIMAL growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the antigens of N. meningitidis?

A

polysaccharide capsule, outer membrane proteins, LOS, pili

17
Q

What is the epidemiology of N. meningitidis?

A

obligate human pathogen
aerosol transmission
serogroups important

18
Q

Who does N. meningitidis affect?

A

all ages

most at risk: infants, young children, late teens

19
Q

*What is the capsule structure of serogroup B of n. meningitidis?

A

*(alpha 2-8)-linked-N-acetyl-neuraminic acid

mimics human structures and is poorly immunogenic

20
Q

What are the different diseases caused by n. meningitidis?

A

meningitis
meningitis w accompanying meningococcemia
meningococcemia w no evidence of meningitis
rarely pneumonia
dz peaks at 6 mos of age
look for purpuric rashes!

21
Q

What are complications/sequelae of inf with N. meningitidis?

A

hearing loss
amputation
Waterhouse-friderichson syndrome
myocardial involvement

22
Q

How does meningococcus enter and survive within the vasculature?

A

capsule and sialylated LOS reduce complement and Ab binding and phagocytosis
lymphocyte, endothelial and epithelial stimulation lead to cytokine release

23
Q

How does the meningococcus penetrate the BBB and enter the meninges?

A

lipid microdomain formation and cytoskeletal rearrangements may enable bound bacteria to resist sheer stress
cytokine damage may increase bacterial transcytosis at all cell barriers
cytokine release following interxn of bacteria with leptomeninges causes meningitis

24
Q

How is n. meningitidis diagnosed?

A

gram stain CSF
cultures CSF, blood (not throat)
molecular methods - PCR

25
Q

How is n. meningitidis treated?

A

pen g
3rd gen cephalosporins
new quinolone resistance reported

26
Q

How is n. meningitidis prevented?

A

vaccines
recently approved for children
none licensed in U.S. for serogroup B
eradication of carriage in close contacts: rifampin, cipro, ceftriaxone

Block 9 - Neuro (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions