MICRO EXAM 2 CH15

Question 1

Oxygen requirement for Streptococcus and entercoccus?

Answer 1

Facultative anaerobic

Question 2

Gram stain result?

Answer 2

GPC in pairs and chains.

Question 3

4 types of hemolytic patterns?

Answer 3

Alpha, beta and gamma

Question 4

Motile or non-motile?

Answer 4

Non-motile

Question 5

Colony morphology?

Answer 5

Small to medium, circular, off-white or grey.

Question 6

Anatomical site for normal flora?

Answer 6

URT, GI and urogenital tract

Question 7

Cell wall structure of Streptococcus and Enterococcus?

Answer 7

Thick layer of peptidoglycan, teichoic acid, carbohydrate layer (lancefield) and capsule.

Question 8

What does alpha hemolytic bacteria release and converts to?

Answer 8

Biliverdin to bilirubin

Question 9

Color and amount of lysing for alpha hemolysis?

Answer 9

Greenish and partial lyses

Question 10

Color and amount of lysing for beta hemolysis?

Answer 10

Complete clearing

Question 11

Color and amount of lysing of gamma hemolysis?

Answer 11

No hemolysis

Question 12

What species are alpha hemolytic?

Answer 12

S. pneumoniae and some viridans strep

Question 13

What species are beta hemolytic?

Answer 13

S. pyogenes and S. agalactiae

Question 14

What 2 other factors does beta hemolysis release that alpha and gamma does not have?

Answer 14

Streptolysin O and Streptolysin S

Question 15

What is streptolysin O?

Answer 15

Oxygen label and immunogenic.
Causes hemolysis on plates.

Question 16

What is streptolysin S?

Answer 16

Oxygen stable and non-immunogenic

Question 17

What part of the bacteria classifies its lancefield grouping?

Answer 17

Carbohydrate region of cell wall?

Question 18

Only what bacteria that exhibit __ hemolysis has lancefield grouping?

Answer 18

Beta hemolytic Streptococcus spp.

Question 19

What Strep Sp. does bacitracin susceptibility test detect for?

Answer 19

S. pyogenes (GAS)

Question 20

What is the bacitracin susceptibility test also known as?

Answer 20

Taxo A disc

Question 21

What Strep Sp. does Opotchin susceptibility test detect for?

Answer 21

S. pneumoniae

Question 22

What is the Optochin susceptibility test also known as?

Answer 22

Taxo P disc

Question 23

How much zone of inhibition is needed to be a positive result for Optochin susceptibility?

Answer 23

Greater than 14mm

Question 24

How long and under what conditions do you incubate Bacitracin and Optochin susceptibility test?

Answer 24

24 hrs at 37ºC in CO2

Question 25

What enzyme does bile solubility test detect for?

Answer 25

Amidase

Question 26

What is the reagent for bile solubility test called?

Answer 26

Sodium desoxycholate

Question 27

What is a positive bile solubility test?

Answer 27

Solubilized suspension or org on plate Clear on tube media

Question 28

What is a negative bile solubility test?

Answer 28

Colony remains intact on plate Turbidity on tube media

Question 28

How do you perform PYR test?

Answer 28

Place colony on disc Drop reagent Wait for result

Question 29

Which Strep Sp. is pos for bile solubility test?

Answer 29

S. pneumoniae

Question 30

What enzyme does PYR hydrolysis test detect for?

Answer 30

L-pyrrolidonyl arylamidase (peptidase(

Question 31

What color is a pos result for PYR?

Answer 31

Pink

Question 32

What color is a neg result for PYR?

Answer 32

No pink/same color as disc

Question 33

What Strep Sp. does PYR test identify?

Answer 33

S. pyogenes or Enterococcus spp.

Question 34

What enzyme does hippurate hydrolysis test detect for?

Answer 34

Hippucate hydrolysis (hippuricase)

Question 35

Neg result of hippurate test?

Answer 35

No purple or clear tube

Question 36

Pos result of hippurate test?

Answer 36

Purple color test tube

Question 37

What Strep Sp. does hippurate test identify?

Answer 37

S. agalactiae (GBS)

Question 38

What organism do you need to perform a CAMP test?

Answer 38

S. aureus

Question 38

Pos CAMP test?

Answer 38

Arrowhead formation with hemolysis

Question 38

How do you do a CAMP test?

Answer 38

Streak S. aureus along the middle of media Perpendicularly streak unknown (but not touching)

Question 39

Neg CAMP test

Answer 39

No arrow head formation

Question 40

What Strep. sp. does a pos CAMP test identify?

Answer 40

S. agalactiae (GBS)

Question 41

What organism grows in bile esculin hydrolysis?

Answer 41

Enterococcus spp. and other group D strep

Question 42

Bile esculin test performed on media plate or slanted tube?

Answer 42

Slanted tube

Question 42

What does Enterococcus do to the media?

Answer 42

Hydrolyzes esculin and grows in bile.

Question 43

Pos Bile esculin result?

Answer 43

Blackening of agar

Question 44

Neg bile esculin result?

Answer 44

No blacking of agar

Question 45

What ability does an organism need to be able to grow in NaCl broth?

Answer 45

Ability to grow in salt

Question 46

What does this test differentiate?

Answer 46

Enterococcus from other Group s strep

Question 47

Pos NaCl result?

Answer 47

Turbidity in broth

Question 48

Neg NaCl result?

Answer 48

No growth (clear broth)

Question 49

What type of hemolytic strep species cause agglutination on slide agglutination test?

Answer 49

Beta hemolytic spp.

Question 50

What does slide agglutination detect and differentiate?

Answer 50

Lancefield grouping in Beta hemolytic spp.

Question 51

6 Virulence factors of S. pyogenes?

Answer 51

Protein F and lipoteichoic acid Hyaluronic acid capsule M protein Hemolysins Streptococcal pyrogenic exotoxin Enzymes

Question 52

What does Protein F and lipoteichoic acid do?

Answer 52

Mediates attachment and adherence to epi cells.

Question 53

What does hyaluronic acid capsule do?

Answer 53

Allows antigen to mask and prevent phagocytosis.

Question 54

What does M protein do?

Answer 54

Allows resistance to phagocytosis and plays a role in adherance.

Question 55

What are hemolysins?

Answer 55

Streptolysin O and S

Question 56

What does streptococcal pyrogenic exotin do?

Answer 56

Cause a rash aka scarlet fever

Question 57

What do enzymes do?

Answer 57

Hyaluronidase solubilized connective issue and streptokinase lysis fibrin clots.

Question 58

Clinical pyodermal infections of S. pyogenes?

Answer 58

Impetigo Erysipelas Cellulitis Wound infections Scarlet fever

Question 59

What test should you do if patient has scarlet fever?

Answer 59

ASO titer

Question 60

Clinical invasive infections of S. pyogenes?

Answer 60

Streptococcal TSST Necrotizing fascitis

Question 61

Normal flora of S. agalactiae?

Answer 61

Urogenital flora in women