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Flashcards in Final; Neisseria Deck (65):
1

Neisseria are the only genus of what that frequently causes disease; and what diseases are an example

gram negative cocci
N. gonorrhoaea
N. menigitidis

2

What type of motility, oxygen level, and location of pathogenesis goes Neisseria prefer

non-motile
aerobes (but can grow aerobically)
obligate human pathogens

3

What techniques are used to diagnose neisseria infections

chocolate agar in presence of CO2
modified thayer-martin agar
catalase and oxidase reaction
sugar fermentations

4

How does meningococci encounter and enter the human host

human nasopharynx
invades mucous membranes
invasion of bloodstream only found in patients lacking complement components C5-C8

5

This is used to attach meningococci to the meninges of the CNS and this is used ti damage host tissues

Type IV pili
lipooligosaccharide (LOS)

6

How does gonococci encounter and enter the human host

asymptomatic carriers greater among women
upon introduction, attach to columnar epithelial of cervix or urethra

7

What are the adhesions of gonococci controlled by

phase variation - presence/absence
antigenic variation - composition

8

What is phase variation of gonorrhoaea

turing on or off the Opa gene which when on results in neutrophil uptake

9

What is antigenic variation of gonorrhoaea

changes in composition or structure of surface molecules (pili; host cell attachment)

10

*How does gonococci multiply rapidly

shed in genital secretions
do not have flagella/not motile
can enter epithelial cells

11

*Extracellular proteases cleave what produced by humans

it cleaves IgA1 removing the Fc receptor and enable stye escape from phagocyotsis

12

How does gonococci spread and mulitply

attachment to non-ciliated
ciliated cell motility slows and ceases
death of ciliated cells

13

This is when non-ciliated microvili engulf bacteria; internalized by "parasite directed endocytosis"

internalization

14

This is when gonococci multiply within vacuoles and then fuse with the basement membrane

intracellular replication
intracellular traffic

15

How does gonococci induce damage

does not secrete exotoxins
LPS and LOS and other cell wall components cause cell damage

16

How does neisseria survive in the host

evasion; LOS is similar to human erythrocyte antigens

17

What are the symptoms of a gonococci infection

localized inflammation
rarely lethal

18

What are the symptoms of a meningococci infection

uncomplicated bacteremic process
metastatic infection of the meninges
overwhelming systemic infecction

19

What is the difference in virulence factors between gonococci and meningococci

meningococci is heavily encapsulated and produces hemolysin

20

A gonococcal infection of the female upper reproductive tract causes what

pelvic inflammatory disease

21

A gonococcal infection of upper reproductive tract in men causes what

epididymitis

22

Disseminated gonococcal infections can result from PID due to endotoxin and cause what symptoms

pustular lesions of skin
inflamed joints/tendons
suppurative arthritis

23

Purpura Fulminans (meningococcus) is disseminated intravascular coagulation due to ability to survive in the blood stream and can cause what symptoms

skin manifestations
meningitis
shock
death
the higher the cytokine response to LOS the greater the risk for damage/death

24

How are neisseria infections treated

most are penicillin resistant (and tetracycline)
resistance to other antibiotics are increasing
antimicrobial chemoprophlaxis is primary prevention

25

*What behavioral methods can be used to prevent neisseria infections

condom use, etc.
partner notification
early diagnosis and treatment

26

*Why are vaccines to gonococci difficult to produce

antigenic and phase variation

27

*What is the vaccine to meningococci

quadrivalent; derived against capsular polysaccharide
tetravalent; polysaccharide protein conjugate (children <2 do not respond)

28

Where does haemophilus (small gram negative cocci) colonize

upper respiratory tract or almost everyone

29

*What does H. influenzae require for growth

hemin (X factor)
NAD+ (V factor)
access to those factors require lysed blood rather than whole blood

30

*Species of haemophilus require what to grow compared with H. influenzae

require only NAD+
can grow in whole blood

31

*What are the tapeable H. influenzae strains

seven antigenically distinct capsular polysaccharides (a, b, c, d, e, e', f)

32

*What is unique about the non-typable H. influenzae strain

it is unencapsulated

33

Which staring of H. influenzae is most virulent and what does it cause

type B (HIB)
bacteremia and meningitis in children younger than 2

34

What does non-typable strains of H. influenzae cause

frequent causes of respiratory tract diseases in infants, children, and adults

35

*What virulence factor of haemophilus makes it resistant to phagocytosis (as long as antibody is not present) and is a basis for the vaccine

polyribosyl ribitol phosphate (PRP) capsule

36

*This virulence factor of haemophilus causes pathogen directed endocytosis

endotoxin

37

*These virulence factors of haemophilus are similar to that of neissseria (gonococcal)

IgA1 protease
Pili and OM proteains

38

What host defenses are used against haemophilus

antibodies to capsule
immunization in infants; PRP conjugated diphtheria toxoid

39

What is the treatment for haemophilus

resistant to penicillins
chloramphenicol = drug of choice
third-generation cephalosporins
corticosteriods reduce complications

40

Where is pseudomonas aeruginosa (gram negative bacillus) found, what is its motility, and its oxygen level

ubiquitous, found in soil and water
motile, polar flagella and pili
aerobic; some strains are anaerobic

41

What are the characteristics of pseudomonas aeruginosa colonies

produce water-soluble pigments that function as antibacterials
fruity or grape-like odor

42

What growth requirements are there for pseudomonas aeruginosa

grow rapidly, very robust
minimal nutritional requirement
can survive in hand creams, soaps, and dilute antiseptics

43

What are the two main types of virulence factors of pseudomonas aeruginosa

persistance and dissemination

44

What type of nutritional aid virulence factors are there for pseudomonas aeruginosa

siderophores (iron binding)
phospholipase C

45

Where wound someone encounter pseudomonas aeruginosa

soil and water;
adheres to veggies and plant matter
in water taps, drains, and wet surfaces
hot tubs

46

How does pseudomonas aeruginosa enter the body

opportunistic infection
does not adhere well to healthy epithelium

47

*After pseudomonas enters the body, the ability to spread and multiply depends on what two things

avoiding phagocytosis
successful adherence to a surface

48

*Adherence of pseudomonas is mediated by what

flagella and pili
interactions with glycolipid (cleaves sialic acid to create asialo GM1; receptor for type 4 pili) on host cells and TLR5

49

What is used to facilitate the spread and multiplication of pseudomonas

polysaccharide capsule
cytolytic exotoxins

50

What does pseudomonas use to damage cells

LPS
exotoxins
multifunctional enzymes; elastase and lasA
type III secretion system delivering virulence factors directly into host cell

51

With pseudomonas, a predisposing factor leads to what

the type of infection; for example,
a local breach in the immune system due to kidney stones will result in an UTI

52

*This may cause decreased sialylation of surface glycolipids of which leads to P. aeruginosa binding

cystic fibrosis transmembrane conductance regulator

53

*Cystic fibrosis and P. aeruginosa also causes dehydration of what, which leads to what

dehydration of respiratory secretions
thick mucus produced which impairs mucociliary system

54

*This shields P. aeruginosa from immune system, however these strains produce less protease and toxins

mucoid exopolyssaccharide (alginate)

55

What mediates pseudomonas and sepsis

LPS

56

What are the three requirements for sepsis

large population of infecting/colonizing organisms
presence of bacterial products that stimulate release of host cytokines
widespread dissemination of microbial products to roses reticuloendothelial system

57

Mortality due to pseudomonas depends on

nature and severity of infection
host defense state
promptness and efficacy of treatment
typically for patients with severe infections, it hover ~50%

58

*True or False
pseudomonas is easily cultured and identified

True

59

*Antibiotic treatment of pseudomonas depends on what

geographic locale;
in some hospitals certain antibiotic-resistant strains predominate

60

*Resistance of pseudomonas is due to what

limited permeability of outer membrane, efflux pumps, and antibiotic resistance genes

61

*What does pseudomonas frequently require to treat it

antibiotic syngerism

62

Listeria is a gram positive rod found where with two types of mobility

intestinal tract of vertebrates, sewage, soil, and water
food-borne pathogen

63

Listeriosis can cause what

infections of fetus
can result in systemic infections such as bacteremia and meningitis
5-10% of adults are asymptomatic carriers

64

What are the virulence factors of Listeria

internalins; mediate adherence and invasion
listerolysin O; escape from vacuoles
phospholipases; escape from vacuoles

65

What is used to prevent and treat Listeria

control of growth in food supply
antibiotics are effective if diagnosed in time