staphylococci

Question 1

common isolates in clinical micro

Answer 1

gram-pos cocci

Question 2

catalase-producing, gram-pos cocci

Answer 2

staphylococcus

Question 3

catalas-producing, coagulase-negative, gram-pos cocci; staphylococci resembles this

Answer 3

micrococci

Question 4

nonmotile, non-spore forming, aerobic/facultatively anaerobic; appear cream-colored, white or rarely light gold, “butterfly-looking”

Answer 4

staphylococci

Question 5

coagulas-producing staphylococci

Answer 5

s. aureus
s.intermedius
s.delphini
s.lutrae
some strains of s.hyicus

Question 6

causes bacterial cell to agglutinate to plasma

Answer 6

clumping factor

Question 7

toxin-induced diseases associated with s.aureus

Answer 7

food poisoning
scalded skin syndrome
toxic shock syndrome

Question 8

known to cause varous health care-acquired or nosocomial infections

Answer 8

s. epidermidis

Question 9

associated mainly with urinary tract infections

Answer 9

s. saprophyticus

Question 10

CoNS occasionally recovered in wounds, septicemia, uti, native valve infections

Answer 10

s. haemolyticus

Question 11

also CoNS, but can occasionally be confused with s.aureus if performing only a traditional slide coag; catheter-related bacteremia & endocarditis

Answer 11

s. lugdunensis

Question 12

important cause of nosocomial infections

Answer 12

s.aureus

Question 13

numerous virulence factor of s.aureus

Answer 13

enterotoxins
cytolytic toxins
cellular components such as protein A

Question 14

heat-stable entotoxins that cause various symptoms, including diarrhea and vomitting

Answer 14

staphylococcal enterotoxins

Question 15

enterotoxins associated with tss

Answer 15

B,C and sometime G and I

Question 16

food poisoning

Answer 16

A,B and D

Question 17

also known as epidermolytic toxin; causes epidermal layer of the skin to slough off and is known to cause staphylococcal sss, sometimes referred to as ritter disease; implicated in bullous impetigo

Answer 17

exfoliative toxin

Question 18

in addition to lysing erythrocytes, can damage platelets and macrophages and cause severe tissue damage

Answer 18

a-hemolysin

Question 19

acts on sphingomyelin in the plasma membrane of erythrocytes and called the “hot-cold” lysin

Answer 19

b-hemolysin

Question 20

enzymes produced by staphylococci

Answer 20

coagulase, protease, hyaluronidase, lipase

Question 21

this enzyme hydrolyzes hyaluronic acid present in the intracellular ground substance that makes up connective tissues, permitting spread of bacteria during infection

Answer 21

hyaluronidase

Question 22

produced by both coagulase-pos and CoNS

Answer 22

lipase

Question 23

primary reservoir for staphylococci is the

Answer 23

human naris

Question 24

colonization also occuring in the

Answer 24

axillae, vagina, pharynx, other skin surfaces

Question 25

transmission of s.aureus may occur by

Answer 25

direct contact with unwashed, contaminated hands and by contact with inanimate objects (fomites)

Question 26

some skin infections caused by s.aureus are

Answer 26

folliculitis, furuncles, carbuncles, bullous impetigo

Question 27

mild inflammation of a hair follicle or oil gland; the infected area is raised and red

Answer 27

folliculitis

Question 28

can be an extension of folliculitis, are large, raised, superficial abscesses

Answer 28

furuncles (boils)

Question 29

occur when larger, more invasive lesions develop from multiple furuncles, can progress into deeper tissues

Answer 29

carbuncles

Question 30

in contrast to furuncles, patients w/ carbuncles often present with

Answer 30

fever and chills, indicating systemic spread of the bacteria

Question 31

highly contagious infection that is easily spread by direct contact, fomites, or autoinoculation

Answer 31

bullousimpetigo

Question 32

bullous exfoliative dermatitis that occurs primarily in newborns and previously healthy young children

Answer 32

scalded skin syndrome

Question 33

rare but potentially fatal, multisystem disease characterized by a sudden onset of fever, chills, vomiting, diarrhea, muscle aches and rash, which can progress to hypotension and shock; associated with the use of highly absorbent tampons

Answer 33

toxic shock syndrome

Question 34

a clinical manif with multiple causes; it is most commonly drug induced, but some cases have been linked to infections and vaccines

Answer 34

toxic epidermal necrolysis

Question 35

type of intoxication resulting from ingestion of a toxin formed outside the body

Answer 35

food poisoning

Question 36

foods that often incriminated in staphylococcal food poisoning include

Answer 36

salads, especially salads containing mayonnaise and eggs; meat or meat products; poultry; egg products; bakery products with cream fillings; sandwich fillings; and dairy products

Question 37

known to occur secondary to influenza virus infection

Answer 37

staphylococcal pneumonia

Question 38

leading to secondary pneumonia and endocarditis has been observed among intravenous drug users

Answer 38

staphylococcal bacteremia

Question 39

occurs as a manifestation secondary to bacteremia

Answer 39

staphylococcal osteomyelitis

Question 40

caused by s.aureus in children, especially with trauma to the extremities, and can occur in patients with a history of rheumatoid arthritis or intravenous drug abuse

Answer 40

septic arthritis

Question 41

infections caused by s.epidermidis are

Answer 41

hospital-acquired

Question 42

predisposing factors are instrumentation procedures in s.epidermidis

Answer 42

catheterization, medical implantation, and immunosuppressive therapy

Question 43

bacterial factor involved in adherence of s.epidermidis, which provides a protective advantage agains host defenses

Answer 43

poly-y-DL-glutamic acid

Question 44

associated with UTIs in young women

Answer 44

s. saprophyticus

Question 45

another CoNS, altho can give a positive clumping factor, but has a negative tube coagulase reaction; more virulent and can mimic s.aureus infections

Answer 45

s.lugdunensis

Question 46

CoNS less commonly seen but opportunistic pathogens

Answer 46

s.warneri, s.capitis, s.simulans, s.hominis, s.schleiferi

Question 47

commonly isolated CoNS; has been reported in wounds, bacteremia, endocarditis, UTIs

Answer 47

s.haemolyticus

Question 48

staphylococcie produce

Answer 48

round, smooth, white, creamy colonies on SBA after 18-24 hours of incu

Question 49

modifies oxidase test that can be used to rapidly differentiate stapth form micrococci

Answer 49

microdase disk

Question 50

important marker for s.aureus

Answer 50

clumping factor, formerly referred to as cell-bound coagulase, causes agglutination in human, rabbit, or pig plasma

Question 51

if no clot appears in tube method of coagulase, it should be

Answer 51

left at room temp and checked the following day; fibrinolysin activity is enhanced at 37 degrees

Question 52

voges-proskauer test

Answer 52

s.aureus (pos) s,.intermedius (neg)

Question 53

resistant to novobiocin

Answer 53

s.saprophyticus

Question 54

rapid agglutination test kits for differentiating s.aureus from cons

Answer 54

BBL staphyloslide, staphaurex, BACTiStaph

Question 55

clsi do not require routine antimicrobial susceptibility testing of s.saprophyticus from urine

Answer 55

becoz isolates typically are sensitive to agents commonly used to treat UTIs

Question 56

require treatment with penicillinase-resistant penicillins, such as nafcillin or oxacillin

Answer 56

penicillin-resistant strains

Question 57

third type of MRSA

Answer 57

health care-associated community-onset methicillin-resistant staphylococcus aureus

Question 58

control of MRSA requires

Answer 58

strict adherence to infection control practices, including barrier protection, contact isolation, and handwashing compliance

Question 59

treatment of choice for MRSA

Answer 59

vancomycin

Question 60

used for detection of methicillin resistance for staph species in the past

Answer 60

oxacillin

Question 61

better inducer of mecA-mediated resistance

Answer 61

cefoxitin

Question 62

growth of the resistant subpopulation is enhanced at

Answer 62

neutral pH, sodiumchloride conc. of 2%-4%, cooler incubation temp (30-32 degrees C), prolonged incubation (up to 48hrs)

Question 63

can be used to screen for MRSA

Answer 63

oxacillin-salt agar plate

Question 64

a macrolide, is frequently used in staphylococcal skin infections

Answer 64

clindamycin