Staphylococci & Micrococci

Question 1

Normal inhabitants of the skin and mucous membranes of humans and other animals

Answer 1

Staphylococci

Question 2

Gram+ cocci
Non-motile
Non-spore forming
Catalase +
Coagulase +
Aerobic or Facultative anaerobe
Bacitracin resistant

Answer 2

Staphylococci

Question 3

Gives staphylococci a positive result in coagulase test

Answer 3

staphylocoagulase

Question 4

Gram+ cocci
Catalase +
Coagulase -
Modified Oxidase +
Bacitracin susceptible
Growth on MSA

Answer 4

Staphylococci

Question 5

Other gram-positive cocci that are occasionally recovered with staphylococci

Answer 5

Rothia mucilaginosa
Aerococcus
Alloiococcus otitis (recovered from the
human middle ear fluid)

Question 6

An important cause of nosocomial infection

Answer 6

S. aureus

Question 7

Heat-stable exotoxins that are able to exhibit symptoms such as vomiting and diarrhea.

Answer 7

Enterotoxins

Question 8

Enterotoxin B

Answer 8

staphylococcal pseudomembranous enterocolitis

Question 9

Enterotoxin F

Answer 9

Toxic shock syndrome

Question 10

It causes the epidermal layer of the skin to slough off

Answer 10

Exfoliative toxin or Epidermolytic toxin

Question 11

known to cause staphylococcal Scalded Skin Syndrome (SSS), sometimes referred to as Ritter Disease

Answer 11

Exfoliative toxin or Epidermolytic toxin

Question 12

Blister formation and sloughing at the top layer of the

skin. Most common in infant and newborns

Answer 12

Scalded skin syndrome or Ritter Disease

Question 13

Formation of large blisters

Answer 13

Bullous impetigo

Question 14

Lyses erythrocytes, damages platelets and macrophages and cause severe
damage

Answer 14

a-hemolysin

Question 15

acts on sphingomyelin using the sphingomyelinase C enzyme in the plasma membrane of
erythrocytes and is also called the “hotcold” lysin

Answer 15

b-hemolysin

Question 16

exhibited in the Christie, Atkins and Munch Petersen (CAMP) test performed in the laboratory to identify group B streptococci

Answer 16

b-hemolysin

Question 17

Exotoxin lethal to polymorphonuclear leukocytes

Answer 17

Panton-Valentine leukocidin (PVL)

Question 18

hydrolyzes hyaluronic acid present in the

intracellular ground substance that makes up connective tissues, permitting the spread of bacteria during infection

Answer 18

Hyaluronidase

Question 19

Has the ability to bind the Fc portion of immunoglobulin G (IgG) which can block phagocytosis andnegate the protective effect of IgG

Answer 19

Protein A

Question 20

Associated with drug reactions and has been linked to
antimicrobials and anticonvulsives, Can be resolved by the administration of steroids early in
the initial stages of presentation, whereas steroids
aggravate SSS

Answer 20

Toxic epidermal necrolysis

Question 21

Rare but potentially fatal, multisystem disease characterized by a sudden onset of fever, chills, vomiting, diarrhea, muscle aches, and rash, which can quickly progress to hypotension and shock

Answer 21

Toxic shock syndrome

Question 22

A life-threatening disorder with erythema, necrosis and bullous detachment of the epidermis resulting in possible sepsis and or death

Answer 22

Toxic Epidermal Necrolysis

Question 23

enterotoxins associated with gastrointestinal disturbances / food poisoning

Answer 23

Enterotoxin A (78%), D (38%), B
(10%)

Question 24

It is considered as normal skin biota but is a common source of hospital acquired infections and often a contaminant in improperly collected blood culture specimens

Answer 24

S. epidermidis

Question 25

common cause of health care-acquired UTIs

Answer 25

S. epidermidis

Question 26

Prosthetic valve endocarditis

Answer 26

S. epidermidis

Question 27

Toxic Epidermal Necrolysis

Answer 27

S. aureus

Question 28

Toxic shock syndrome

Answer 28

S. aureus

Question 29

Associated with UTIs in young women

Answer 29

S. saprophyticus

Question 30

Obligate anaerobe staphylococci

Answer 30

S. saprophyticus

Question 31

Scalded skin syndrome or Ritter Disease

Answer 31

S. aureus

Question 32

Known to contain the gene mecA that encodes oxacillin resistance

Answer 32

S. lugdunensis

Question 33

ferments mannitol and produces a

yellow halo on MSA as a result of acid production altering the pH

Answer 33

S. aureus

Question 34

Staphylococci Isolation

Answer 34

Sheep's blood agar
Mannitol Salt Agar
Columbia colistin-nalidixic acid agar (CNA)
Phenylethyl alcohol (PEA) agar
CHROMagar

Question 35

Produces round, smooth, white, creamy colonies on SBA after 18 to 24 hors of incubation at 35C to 37C / Buttery looking

Answer 35

Staphylococci