virulence

Question 1

which virulence factorr is key for staph aures ?

Answer 1

protein A

Question 2

how does protein A work ?

Answer 2

inhibits phagocytosis by binding the Fc portion prevents the activation of the immune system and no opsonization happens and no compliment is activated

Question 3

what bacteria are associated with the IgA protease cleavage factor ?

Answer 3

SHiN
s pneumonia
haemophilus influenza b
neisseria

Question 4

how does IgA proteas works ?

Answer 4

cleavage of gA allows for thee invasion of mucosal surfaces

Question 5

what bacteria uses thee M protein as a virulence factor ?

Answer 5

group A strep
associated with rheumatic fever
due too molecular mimicry

Question 6

what are the post strep complicatons ?

Answer 6

rheumatic heat disease
glomerulonephritis

Question 7

what determines what post strep complication you get ?

Answer 7

depends on he M protein subtype
strains that cause impetigo will result n GN
strains that cause pharyngitis will cause rheumatic fever

Question 8

main differences between endo and exotoxins ?

Answer 8

endotoxins are only secreted by gram negative bacteria when they die (LPS)

exotoxins are proteins synthesised by bacteria

Question 9

what are the feeatures associated with endotoxins ?

Answer 9

all produced by gram negative bacteria
all have a lipid a core
O antigen

Question 10

how do endotoxin present as illness?

Answer 10

they allow for the release of IL 2 and TNF

Question 11

why cant we make vaccines against endotoxins ?

Answer 11

weak antibody response

Question 12

what are the immune responses associated with LPS ?

Answer 12

macrrophage - IL 1 , TNF and nitrric ooxide
complement - C3a releasee , C5a relas
tissuee factor - coagluation and DC

Question 13

what is thee endotoxin receptor ?

Answer 13

CD14

Question 14

what are the different mechanisms associated with exotoxins ?

Answer 14

inhibition of protein synthesis
increase fluid secretion
inhibit phagocytic ability
inhibit release of neurotransmitters

Question 15

which bacteria are associated with exotoxins that inhibit protein synthesis ?

Answer 15

diphtheria
pseudomonas
shigella
enterohaemorrrhagic E coli

Question 16

what are the toxins associated with diphtheria and pseudomonas and what is their mechanism of action ?

Answer 16

diphtheria toxin
exotoxin A
both allow for the ADP ribosylation off EE2F elongation factor

Question 17

what is the toxin associated with shigella and what is thee mechanism of action ?

Answer 17

shiga toxin binds to the 60 S subunit off ribosomes
shiglla invadess thee host cell

Question 18

what is the presentation off diphtheria ?

Answer 18

membranous lymphadenopathy
bulls neck

Question 19

what is the presentation of shigella infection ?

Answer 19

infectious diarrhea

Question 20

what s thee virulence factor associated with E E.coli ?

Answer 20

shiga like toxin
also binds to 60 S portion of ribosomes
causes bloody diarrhea

Question 21

what are the two classic examples associated with systemic reactions to endotoxins ?

Answer 21

meningococcemia
gram negative sepsis

Question 22

what is the man mechanisms of disease n shigella vs in E.Ecoli?

Answer 22

shigella - invasion of inteestiinal cells
e.col - through toxn releasee

Question 23

what happens upon the release of shiga toxin into the blood ?

Answer 23

hemolytic uremic syndrome
only associated with E E coli

Question 24

what are the bacteria that release exotoxins that. increase fluid secretion ?

Answer 24

entrotoxigenic e coli
bacillus anthrax
cholera

Question 25

how do clls in the GI tract secrete fluids ?

Answer 25

the more chlorine out the more water in

Question 26

what is the chlorine controlled by in the GI tract ?

Answer 26

CFTR gene

Question 27

what must bee done to increase chlorine secretion ?

Answer 27

activate Gs or AC

Question 28

what are the toxins associated with enterotoxigenic e coli ?

Answer 28

heat labile exotoxin - activate cAMP heat stable exotoxin- activates cGMP

Question 29

what are the three proteins associated with bacillus anthrax ?

Answer 29

protective antigen lethal factoor edema factor

Question 30

what is the edma toxin compromised of ?

Answer 30

PA + EF

Question 31

what. does edema toxin mimic ?

Answer 31

adenyl cyclase

Question 32

what is the presentation of anthrax ?

Answer 32

lung affection - necrotizing pneumonia skin affection - black escharin GI - ulcers

Question 33

what is thee toxin associated with cholera ?

Answer 33

cholera toxin overactivates cAMP Gs is always active

Question 34

what are the bacteria that inhibit phagocytosis ?

Answer 34

bordatella pertussis pertussis toxin G inhibitory protein inactivation so over activation of adenylate cyclase

Question 35

which bacteria are associated with the inhibition of neurotransmitters and the associated toxins ?

Answer 35

clostridium tetani - tetanospasmin clostridium botulinum -botlinium toxin

Question 36

what is the mechanism of action associated with the toxins from bacteria that inhibt neurotransmitters ?

Answer 36

tetanospasmin - rigid paralysis botulinim - flaccid paralysis

Question 37

what type of cells does tetanospasm work on ?

Answer 37

reenshaw cells

Question 38

what bacteria release exotoxins associated with the lysis of cell membrane and what are the toxins associated ?

Answer 38

clostridium perferengens - alpha toxin strep pyogens - streptolysin O

Question 39

what is the mechanism of action off alpha toxin ?

Answer 39

phospholipase that degrades tissue and cell membranes causes myonecrosis gas gangrene

Question 40

what is the mechanism off action of streptolysin O ?

Answer 40

protein that degrades cell memb

Question 41

what is seen on blood agar with strep pyogens ?

Answer 41

double zone of hemolysis

Question 42

what are the toxoid vaccines ?

Answer 42

DTaP diphtheria and tetanus and acellular pertussis

Question 43

what are superantigens ?

Answer 43

a type of exotoxin that causes a huge recruitment of T cells hue release of IL 2 and IFN gamma

Question 44

what are the 2 bacteria associated with superantigens ?

Answer 44

staph aureus TSST 1 strep pyogens A or C

Question 45

what clinical scenarios are associated with TSS ?

Answer 45

staph and packing women with tampon surgical wound with packing

Question 46

how can TSS seperated from sepsis ?

Answer 46

TSS , resemble a sunburn with desquamation of the hand ad the soles diarrhea is also common in TSS but not in sepsis

Question 47

what is staph TSS commonly associated with ?

Answer 47

strep TSS