STREPTOCOCCUS

Question 1

Inhabit various sites, notably the upper respiratory
tract, and live harmlessly as commensals.

Answer 1

Streptococcus and Enterococcus

Question 2

More pronounced growth on media enriched with
blood or serum

Answer 2

Streptococcus

Question 3

This classification scheme was developed in
the 1930s

Answer 3

Rebecca Lancefield.

Question 4

Produces a zone of partial hemolysis with a greenish
discoloration around the colonies on blood agar
● Streptococci producing α-hemolysis are also known as

Answer 4

Alpha-hemolytic (α) Streptococci

Question 5

Produces a complete hemolysis
- Sharply defined, clear, colorless zone of
hemolysis around the colony induced by
bacterial hemolysins
- No red blood cell is visible on microscopic
examination in the clear zone of complete
hemolysis.

Answer 5

ß-hemolysis

Question 6

constitutes the principal marker for
potentially pathogenic streptococci in cultures of throat
swabs or other clinical samples.

Answer 6

ß-hemolysis

Question 7

● Produce no hemolysis on blood agar

Answer 7

Gamma (γ) or Non-hemolytic Streptococci

Question 8

is an important organism of Gamma (γ) or Non-hemolytic Streptococci

Answer 8

Enterococcus faecalis

Question 9

beta h members

Answer 9

S. equisimilis
S. pyogenes
S. agalactiae
E. faealis

Question 10

based on the serological
properties of the streptococci

Answer 10

A, B, C, D, and G Lancefield Grouping

Question 11

Organisms in possess the same
antigenic C-carbohydrate organisms.

Answer 11

Group A

Question 12

group a

Answer 12

pyogenes

Question 13

group b

Answer 13

agalactiae

Question 14

group c

Answer 14

s.equisimilis, ewqui, dysogalactiae, zoopidimidus

Question 15

group d

Answer 15

enteroccoci, non entero

Question 16

group does not grow
under 10°C but grows best at 37°C.

Answer 16

Pyogenic and viridans

Question 17

group grows at all temperatures

Answer 17

Entero

Question 18

group grows best at 10°C and 37°C,
but does not grow at 45°C

Answer 18

Lactic

Question 19

All of the grows best at optimum
temperature of 37°C

Answer 19

streptococci

Question 20

part of cell wall ps strep; antiphagocytic

Answer 20

m protein

Question 21

(oxygen labile)
- highly immunogenic; measured using ASO
(antistreptolysin O) test

Answer 21

Streptolysin O

Question 22

(oxygen stable)
- nonimmunogenic

Answer 22

Streptolysin S

Question 23

M-protein is genes of what strep specie

Answer 23

s.pyogenes

Question 24

formerly
called erythrogenic toxin; causes Scarlet Fever

Answer 24

Streptococcal pyrogenic exotoxin

Question 25

Streptococcal pyrogenic exotoxin

Answer 25

Nephrogenic toxin

Question 26

camp factor produced by; heat stable protein; enhances the beta-hemolysis of staph. aureus

Answer 26

S. agalactiae

Question 27

small, transparent and smooth; beta-hemolytic; when grows in sheep's blood agar

Answer 27

S. pyogenes

Question 28

grayish white mucoid colonies; beta-hemolytic (small zone)

Answer 28

S. agalactiae

Question 29

The __test is a particularly important test used to determine whether the gram positive cocci is a staphylococci or a streptococci.

Answer 29

catalase

Question 30

Differentiates Group A Streptococci from other Streptococci

Answer 30

Bacitracin Susceptibility Test (Taxo A)

Question 31

Positive: arrowhead hemolysis [Group B Strep] or bowtie appearance [S. agalactiae]

Answer 31

camp test

Question 32

Positive: Cherry Red/Pink ● Test for Group A and Group D Streptococci test is useful in the identification of group A, beta hemolytic streptococci and the streptococcus pyogenes.

Answer 32

PYR hydrolysis

Question 33

● Test for Group B Streptococci ● Medium: Broth with hippurate ● Positive: Purple (S. agalactiae)

Answer 33

Hippurate Test

Question 34

indicator of hippurate glycine is oxidated by this which turns the broth purple

Answer 34

ninhydrin

Question 35

● Positive: blackening of medium [Group D] ● Differentiate Group D from Beta-hemolytic is widely used for the differentiation of enterococci and group B streptococci which are bile tolerant and can hydrolyze esculin to esculetin with the help of the enzymes esculinase from non-group D viridans groups streptococci which grow poorly on bile

Answer 35

Bile Esculin Tes

Question 36

● Further test from Bile Esculin Test ● To identify Enterococci ● Positive: Turbid [Enterococci] ● Negative: Clear/Transparent [Non-enterococci]

Answer 36

Salt Tolerance Test (6.5% NaCl)

Question 37

● Reagent: paradimethylaminocinnamaldehyde reagent ● Positive color: Red color this test identify which group

Answer 37

● Positive: Viridans Streptococci

Question 38

based from the previous question, which test is conducted

Answer 38

Leucine Aminopeptidase Test

Question 39

SXT or sulfamethoxazole this susceptibility test in conjunction with bacitracin is used for the presumptive identification of beta hemolytic streptococci on blood agar. The resistance of sulfamethoxazole is used for the primary recovery of group ________streptococci from specimens with mixed culture

Answer 39

A and B

Question 40

BACTERIAL PHARYNGITIS ● “Strep throat” The most common clinical manifestations of streptococcus _ are pharyngitis and tonsillitis.

Answer 40

pyogenes

Question 41

a localized skin disease, begins as small vesicles that progress to weeping lesions; inoculation of organisms through minor abrasions or insect bites

Answer 41

impetigo

Question 42

- followed by deeper invasion of streptococci; life-threatening; with bacteremia or sepsis Patients with peripheral vascular disease or diabetes – leads to gangrene

Answer 42

cellulitis

Question 43

s a rare infection of the skin and subcutaneous tissues observed frequently in elderly patients

Answer 43

Erysipelas

Question 44

- cause by streptococcal pyrogenic exotoxin - Diffuse red rash on upper chest and spreads to the trunk and extremities - Infection with strains of streptococcus pyogenes that produce streptococcal pyrogenic exotoxins can result in

Answer 44

scarlet fever

Question 45

“Flesh-eating disease or syndrome”, “Suppurative fasciitis”, “Hospital gangrene”, “Necrotizing erysipelas” ● An invasive infection characterized by rapidly progressing inflammation and necrosis of the skin, subcutaneous fat, and fascia

Answer 45

NECROTIZING FASCIITIS

Question 46

A condition in which the entire organ system collapses, leading to death Caused by a type of streptococcal pyrogenic exotoxin – SpeA

Answer 46

STREPTOCOCCAL TOXIC SHOCK SYNDROME

Question 47

● GAS are susceptible to (drug of choice for treatment)

Answer 47

penicillin

Question 48

If allergic to penicillin -

Answer 48

erythromycin will do

Question 49

● Todd-Hewith Broth ● Significant cause of invasive disease in newborn

Answer 49

● Todd-Hewith Broth ● Significant cause of invasive disease in newborn

Question 50

Ends of the cells are slightly pointed (oval or lancet shape) BHIA, TSA with 5% sheep RBCs or Chocolate Agar are necessary for good growth - SBA – large zone of alpha-hemolysis

Answer 50

S. pneumoniae