Staphylococci

Question 1

catalase-producing, gram-positive
cocci.

Answer 1

Staphylococci

Question 2

catalase-producing, coagulase negative, gram-positive cocci found in the environment and as members of the indigenous
skin microbiota

Answer 2

Micrococci

Question 3

What color of pigment does micrococci produce?

Answer 3

yellow pigment

Question 4

Other gram-positive cocci that are occasionally recovered with staphylococci include

Answer 4

Rothia mucilaginosa, Aerococcus, and Alloiococcus
otitis

Question 5

staphylococci are nonmotile, non–spore-forming, and
aerobic or facultatively anaerobic except for?

Answer 5

S. Sacchorolyticus

Question 6

colonies of staph are produced after how many hours?

Answer 6

18-24 hours

Question 7

what is the appearance of staph?

Answer 7

white or gold and buttery looking

Question 8

what is the most clinically significant species of staph?

Answer 8

S. aureus

Question 9

staphylococci that are coagulase positives are?

Answer 9

s. aureus s. intermedius, s. delphinin, and s. lutrae

Question 10

staphylococcus can grow in what medium?

Answer 10

MSA, BAP, and CNA

Question 11

what test is used to differentiate staphylococcus spp. to streptococcus spp.

Answer 11

catalase test

Question 12

principle of catalase:
catalase + _____ - H2O + O

Answer 12

H2O2

Question 13

used to differentiate S. aureus from other Staphylococci; definitive and most reliable method for
detection of the species

Answer 13

coagulase test

Question 14

it detects bound coagulase/clumping factor?

Answer 14

slide coagulase

Question 15

what kind of plasma is used in slid coagulase?

Answer 15

rabbit’s plasma

Question 16

detects free coagulase/ coagulase reacting factor

Answer 16

tube coagulase

Question 17

latex particles are coated with sheep red cells or human plasma fibrinogen and IgG which will react with clumping factor cells and protein A of S. aureus

Answer 17

latex agglutination

Question 18

what is the inhibitor of MSA

Answer 18

7.5%-10% NaCl

Question 19

What is the indicator of MSA

Answer 19

phenol red

Question 20

s. aureus in MSA (appearance)

Answer 20

yellow zone around colonies

Question 21

s. epidermis in MSA (appearance)

Answer 21

red zone around colonies

Question 22

causes various cutaneous infections and purulent
abscesses that can progress to deeper abscesses
and produce bacteremia and septicemia

Answer 22

s. aureus

Question 23

Staphylococci that do not produce coagulase are
referred to as?

Answer 23

CoNS

Question 24

known to cause various health care-acquired or nosocomial infections

Answer 24

s. epidermis

Question 25

associated mainly with urinary tract infections (UTIs), predominately in adolescent girls and young women

Answer 25

s. saprophyticus

Question 26

is a CoNS occasionally recovered in wounds, septicemia, UTIs, and native valve infection

Answer 26

s. haemolyticus

Question 27

is also a CoNS, but it can occasionally be confused with S. aureus if performing only a traditional slide coagulase method using plasma

Answer 27

s. lugdunensis

Question 28

– interferes with opsonization and phagocytosis from neutrophils and activation of complement; immunogenic; binds to Fc fraction of most IgG

Answer 28

protein a

Question 29

resist phagocytosis by neutrophils; enhance organism’s ability to bind to host cells and prosthetic

Answer 29

capsular polysaccharide

Question 30

activate complement, enhance neutrophils, chemotaxis, and formation of opsonin; has clumping factor adhesins & collagen-binding protein

Answer 30

peptidoglycan & teichoic acid

Question 31

are heat-stable exotoxins that cause various symptoms, including diarrhea and vomiting

Answer 31

enterotoxins

Question 32

enterotoxins are stable at

Answer 32

100°C for 30 minutes

Question 33

Staphylococcal food poisoning: most commonly caused by enterotoxins?

Answer 33

A B D

Question 34

linked to staphylococcal pseudomembranous enterocolitis

Answer 34

Enterotoxin B

Question 35

causes nearly all cases of menstruating associated TS

Answer 35

Toxic shock syndrome toxic 1

Question 36

known to cause staphylococcal SSS, sometimes referred to as Ritter disease. ▪ also been implicated in bullous impetigo

Answer 36

Exfoliative toxin

Question 37

coats neutrophils with fibrin which protects organism from phagocytosis.

Answer 37

bound coagulase

Question 38

– lyses and inactivate penicillin through breakdown of B-lactam; resistance to ampicillin and other antibiotics

Answer 38

penincillinase

Question 39

lyses RBC; responsible to B-hemolysis

Answer 39

hemolysin

Question 40

– exotoxin which destroys WBC; contributes to the invasiveness of the organism by suppressing phagocytosis; involved in community acquired MRSA

Answer 40

panton-valentine leukocidin

Question 41

CoNS that are hospital acquired and most common cause of UTI and prosthetic valve endocarditis and other prosthetic devices

Answer 41

S. epidermis

Question 42

key component that are responsible in pathogenesis and promote adhesion in surfaces

Answer 42

biofilm production

Question 43

what CoNS have creamy and white colonies and prose gamma hemolytic which produce slime and adheres to the agar surface

Answer 43

S. epidermis

Question 44

cause UTU such as pyelonephritis and cystitis especially in sexually active young women and cause of catheter associated UTI in men and women

Answer 44

s. saprophyticus

Question 45

they have the ability to adhere epithelial cells in urinary tract and urethral cells

Answer 45

s. saprophyticus

Question 46

white colonies, gamma hemolytic, and resistant to novobiocin

Answer 46

s. saprophyticus

Question 47

can be more virulent and can mimic the infections of s. aureus

Answer 47

s. lugdunensis

Question 48

s. lugdenensis have the ability to resists oxacillin. what gene does this CoNS have

Answer 48

meCA gene

Question 49

pathogen that cause endocarditis, septicemia, and soft tissue infections

Answer 49

s. lugdunensis

Question 50

CoNS that have white to large. smooth, glossy edge with slight domes center, unpigmented or cream to yellow orange columns

Answer 50

s. lugdunensis

Question 51

enumerate the penicillin resistance of MRSA

Answer 51

nafcillin, oxacillin, methicillin, and amoxicillin

Question 52

what is the treatment of choice for MRSA

Answer 52

vancomycin

Question 53

MRSA detection that are commercially available and mauve color as their end product

Answer 53

chromogenic

Question 54

latest CLSI M100 detection test for MRSA

Answer 54

cefoxitin disk screen test

Question 55

what is the gold standard and most sensitive for detection mecA or PBP2a

Answer 55

PCR

Question 56

used to differentiate from staphylococcus to micrococcus

Answer 56

modified oxidase test

Question 57

if the test result came out in a dark blue color. what is the interpretation?

Answer 57

positive and micrococcus

Question 58

if there is no color change in modified oxidase test. what is the interpretation

Answer 58

negative and staphylococcus

Question 59

what is the next course of action is the organism is positive and catalase test?

Answer 59

coagulase test

Question 60

what is the next course of action if the organism is negative in coagulase test?

Answer 60

oxidase test

Question 61

what staph spp. is resistant to novobiocin?

Answer 61

s. saprophyticus

Question 62

what is the best inducer of mecA mediated resistance?

Answer 62

cefoxitin

Question 63

what is the frequently used in staphylococcal skin infections?

Answer 63

Clindamycin

Question 64

most clinically significant and commonly recovered species in the CoNS?

Answer 64

s. epidermis and s. saprophyticus

Question 65

s. epidermis is known to cause what kind of infections?

Answer 65

nosocomial infections