Staphylococcus And Other

Question 1

Endogenous strain: Sterile urinary tract, notably in young, sexually active female

Answer 1

Staphylococcus saprophyticus

Question 2

Endogenous strain: sterile site by traumatic introduction (e.g., surgical wound or microabrasions

Answer 2

Staphylococcus aureus

Question 3

Endogenous strain: sterile site, by implantation of medical devices (e.g. shunts, prosthetic devices)

Answer 3

Staphylococcus epidermidis

Question 4

Produce polysaccharide capsule (inhibits phagocytosis)

Answer 4

S. aureus and S. epidermidis

Question 5

Disrupts smooth muscle in blood vessels. Toxic to erythrocytes, leukocytes, hepatocytes, and platelets

Answer 5

Alpha toxin

Question 6

Work in conjunction with alpha toxin. Heat-labile sphingomyelinase which catalyzes hydrolysis of membrane phospholipids resulting in cell lysis.

Answer 6

Beta toxin

Question 7

Cytolytic to erythrocytes. Produced by S. haemolyticus, S. epidermidis, S. aureus (SHEA)

Answer 7

Delta toxin

Question 8

Associated with Panton-Valentine Leukocidin (PVL)

Answer 8

Gamma toxin

Question 9

Resistant to hydrolysis by the gastric and intestinal enzymes

Answer 9

Heat-stable enterotoxin

Question 10

Scalded skin syndrome (Ritter disease), pemphigus neonatorum, food poisoning, folliculitis, furuncles, and carbuncles

Answer 10

S. aureus

Question 11

Virulence factors: polysaccharide capsule, peptidoglycan, protein A, heat-stable TSST-1

Answer 11

S. aureus

Question 12

Virulence factor: exopolysaccharide “slime” or biofilm, delta toxin

Answer 12

S. epidermidis

Question 13

Endocarditis involving prosthetic cardiac valves; infection at intravascular catheter sites, other infections associated with CSF shunts, prosthetic joints, vascular grafts, post surgical ocular infections

Answer 13

S. epidermidis

Question 14

Extremely low virulence. Rarely cause infections in humans; implications in otitis external and otitis media

Answer 14

Micrococcus, etc.

Question 15

Recover aerobic and anaerobic bacteria

Answer 15

Amies transport media

Question 16

Recover aerobic and anaerobic bacteria; charcoal neutralized bacterial toxins

Answer 16

Amies with charcoal transport media

Question 17

Recovers anaerobes and micro aerobic

Answer 17

Anaerobic transport media

Question 18

Recover enteric bacteria

Answer 18

Cary-Blair

Question 19

Recover gastrointestinal parasites; acceptable for immunoassays

Answer 19

Formalin (5% -10%); polyvinyl alcohol (PVA); sodium-acetate-acetic acid formali (SAF); Total-fix; Eco-fix

Question 20

Media of choice for Staphylococci, Micrococci, related organisms

Answer 20

BAP, Thioglycollate, Dextrose, Brain-Heart infusion broth

Question 21

Resembles S. lugdunensis in 5% SBA

Answer 21

Staphylococcus wameri

Question 22

Beta hemolytic in 5% SBA

Answer 22

S. aureus, S. haemolyticus, S. lugdunensis

Question 23

Wide variety of pigments (white, tan, yellow, orange, pink) in SBA

Answer 23

Micrococcus spp., and related organisms

Question 24

Separate S. aureus from other species collectively referred to as coagulase-negative streptococci.

Answer 24

Coagulase production

Question 25

Novobiocin resistant with inhibition zone diameter of <10mm

Answer 25

Staphylococcus saprophyticus

Question 26

Used to discern between methicillin-sensitive S. aureus (MSSA) and MRSA

Answer 26

Matrix- Assisted Desorption Ionization Time of Flight

Question 27

Selective and differential for identification of MRSA

Answer 27

CHROMagar

Question 28

MRSA colonies in CHROMagar

Answer 28

Mauve color

Question 29

Visible growth @ 35C in CO2 or ambient air within 24 hours of inoculation

Answer 29

5% sheep blood and chocolate agars

Question 30

Require at least 48-72 hrs before growth is detected

Answer 30

MSA and other selective media

Question 31

Requires storage and incubation in dark for best results

Answer 31

CHROMagar