FA Gram + Cocci Flashcards Preview

Micro > FA Gram + Cocci > Flashcards

Flashcards in FA Gram + Cocci Deck (63):
1

Gram positive cocci in clusters

Staph aureus

2

What is the virulence factor for S aureus?

Protein A

3

How does protein A work?

Binds Fc-IgG, inhibiting complement fixation and phagocytosis

4

TSST is a superantigen that binds to WHAT causing WHAT?

MHC II and T cell receptor --> poly T cell activation

5

Presentation of toxic shock syndrome

Fever,
Vomiting,
Rash,
Desquamation,
Shock,
End organ failure

6

S aureus food poisoning is due to ingestion of

preformed antigen

7

What types of inflammatory diseases can staph aureus cause?

skin infections, organ abscesses, penumonia

8

What types of toxin-mediated diseases can staph aureus cause?

Toxic shock syndrome (TSST-1)
Scalded skin syndrome (exfoliative toxin)
Rapid onset food poisoning (enterotoxins)

9

What is the toxin that causes toxic shock syndrome?

TSST-1

10

What is the toxin that causes scalded skin syndrome?

exfoliative toxin

11

What is the toxin that causes staph aureus rapid-onset food poisoning?

enterotoxins

12

Name an important cause of serious nosocomial and community-acquired infections

MRSA

13

Why is MRSA resistant to beta lactams?

Altered penicillin-binding protein

14

5 broad types of infections caused by MRSA (this is a read my mind question)

1. Inflammatory disease
2. Toxin-mediated disease
3. MRSA
4. Acute bacterial endocarditis
5. osteomyelitis

15

How can staph lead to abscess?

forms fibrin clot around self

16

Staph make catalase because they have more staff (compared with strep). Bad staph (aureus) make

coagulase and toxins

17

Infects prosthetic devices and intravenous catheters by producing adherent biofilms. Component of normal skin flora; contaminates blood cultures

Staph epidermidis

18

What is the most common cause of MOPS:
meningitis
otitis media (in kids)
pneumonia
sinusitis

Strep pneumo

19

strep pneumo is the most common cause of what four conditions

meningitis
otitis media (in kids)
pneumonia
sinusitis

20

Lancet-shaped, gram positive diplococci

Strep pneumo

21

encapsulated bacteria that carries IgA protease

Strep pneumo

22

Rusty sputum pneumonia

Strep pneumo

23

Sepsis in sickle cell

Strep pneumo

24

Sepsis in asplenic pt

strep pneumo

25

to what is strep pneumo sensitive?

s pneumo MOPS are Most OPtochin Sensitive

26

Strep pneumo would have no virulence without its

capsule

27

Dental caries

Strep mutans (viridans, group D)

28

subacute bacterial endocarditis

Strep sanguis (viridans, group D)

29

type of hemolysis for strep viridians (group d)

alpha

30

how to differentiate viridans from strep pneumo

Viridans is optochin resistant, but strep pneumo is optochin sensitive

31

How does s sanguis stick to damaged valves by making

glycocalyx

32

viridans are normal flora where?

oropharynx

33

Viridians group strep live in the mouth because they are not afraid .... (joke)

of the chin! (optochin resistant)

34

strep pyogenes is also called

group A strep

35

pyogenic manifestations of strep pyogenes

pharyngitis, cellulitis, impetigo

36

toxigenic manifestations of strep pyogenes

scarlet fever, toxic shock-like syndrome, necrotizing fasciitis

37

immunologic manifestations of strep pyogenes

rheumatic fever, acute glomerulonephritis

38

How to differentiate strep pyogenes and agalactiae

bacitracin (pyogenes is sensitive)

39

BLANK enhances host defenses against Strep pyogenes, but can also give rise to rheumatic fever

ANTIBODIES to M protein (note: imm response NOT bacteria that cause rheumatic fever)

40

how would you detect a recent s pyogenes infection?

ASO titer

41

What are the jones criteria to diagnose rheumatic fever

Joints (polyarthritis)
s chorea

42

Strep pyogenes PHaryngitis can result in (the stupidest mnemonic ever)

rheumatic PHever and glomerulonePHritis

43

BLANK more commonly precedes PSGN than pharyngitis

impetigo

44

scarlet rash SPARING face, strawberry tongue, scarlet throat

scarlet fever

45

beta hemolytic + bacitracin resistant =

Strep agalactiae (group B strep)

46

colonizes vagina; causes pneumonia, meningitis, and sepsis, mainly in babies

Strep agalactiae (group B strep)

47

S agalactiae produces what factor?

CAMP factor (note this is not cyclic AMP)

48

CAMP factor does what?

enlarges area of hemolysis formed by S aureus (ugh wait what? why is staph aureus here too?)

49

what test would you do to confirm strep agalactiae presence?

hippurate

50

because group B hits babies, you should screen pregnant women at

35-37 weeks

51

if a pregnant woman has group B positive cultures, she should receive

intrapartum penicillin prophylaxis

52

There are two general classes of group D streptococci

Enterococci
Strep bovis

53

name two important enterococci (group B strep)

E faecalis
E faecium

54

Enterococci are normal colonic flora that are all resistant to what?

Penicillin G

55

Three types of infections caused by enterococci

1. UTI
2. Biliary tract infections
3. Subacute endocarditis

56

Lancefield grouping is based on differences in the

C carbohydrate on the bacterial cell wall.

57

Lancefield group D includes

enterococci and nonenteroccal group D streptococci

58

group D strep hemolysis?

variable

59

To distinguish enterococci from nonenterococcal group D

enteroccci can grow in 6.5% saline and bile

60

Some enterococci have become resistant to WHAT --> important cause of nosocomial infection

Vancomycin --> VRE

61

Colonizes the gut; can cause bacteremia and subacute endocarditis in colon cancer patients

Strep bovis (group D)

62

Bovis in the blood =

cancer in the colon

63

word association: strep bovis

colon cancer