4. Family Streptococcaceae Flashcards Preview

Elsevier Bacteriology (RVSP) > 4. Family Streptococcaceae > Flashcards

Flashcards in 4. Family Streptococcaceae Deck (53):
1

Catalase reaction of the family Streptococcaceae

Catalase negative

2

Type of hemolysis; conversion of hemoglobin to methemoglobin resulting in a green zone in the blood agar around a colony

Alpha (α)

3

Type of hemolysis; lysis of sheep RBCs in the blood agar plates

Beta (β)

4

Lancefield grouping; nonhemolytic

Gamma (γ)

5

Lancefield group of Streptococcus pyogenes

Group A

6

Causative agent of pharyngitis: "strep throat"

S. pyogenes

7

2 complications of S. pyogenes infections

Rheumatic fever
Acute glomerulonephritis

8

S. pyogenes sequelae; can cause chronic, progressive damage to the heart

Rheumatic fever

9

S. pyogenes sequelae; circulating immune complexes deposit in glomeruli; inflammatory response causes damage

Acute glomerulonephritis

10

Virulence factor of S. pyogenes; for attachment

M protein
Lipoteichoic acid

11

Virulence factor of S. pyogenes; inhibits phagocytosis

Hyaluronic acid capsule

12

S. pyogenes toxin that causes the rash in scarlet fever

Pyrogenic (erythrogenic) toxin

13

Enzyme by S. pyogenes; lyses fibrin clot

Streptokinase

14

Enzyme by S. pyogenes; dissolves purulent/fibrinous secretions

Streptodornase (DNase B)

15

Streptolysins by S. pyogenes

Streptolysin O and S

16

Microscopic appearance of S. pyogenes

Gram-positive cocci in chains

17

Colony morphology of S. pyogenes

Small
Transparent
Smooth
β-hemolytic colonies

18

Bacitracin susceptibility of S. pyogenes

Bacitracin susceptible

19

L-pyrrolidonyl arylamidase (PYR) reaction of S. pyogenes

PYR positive

20

Penicillin susceptibility of S. pyogenes

Penicillin susceptible

21

Lancefield group of S. agalactiae

Group B

22

Body parts/organs where S. agalactiae is normal flora

Female genital tract
Gastrointestinal tract

23

Diseases caused by S. agalactiae

- Pneumonia in elderly
- UTI
- Neonatal sepsis and meningitis

PUN

24

When is S. agalactiae transmitted vertically from the mother?

In early-onset neonatal disease (0-6 days)

25

When is S. agalactiae transmitted horizontally?

In late-onset meningitis (7 days - 3 months age)

26

Virulence factors for S. agalactiae

Capsule
Hemolysin
Hyaluronidase
Protease

CHHP

27

Colony morphology of S. agalactiae

Grayish-white
Slightly mucoid
Larger colony than group A
Small-zone of β-hemolysis

28

Hippurate reaction of S. agalactiae

Hippurate positive

29

CAMP test reaction of S. agalactiae

CAMP test positive

30

Penicillin susceptibility of S. agalactiae

Penicillin susceptible

31

Group D Streptococcus is normal flora in the

GI tract
Urogenital tract

32

Clinical significance of Group D Streptococcus

Bacteremia
Endocarditis

33

Examples of Group D Strep

S. gallolyticus (bovis)
S. equinus

34

Colony morphology of Group D Strep

Small
White colonies with hemolysis on blood agar

35

Bile esculin reaction of Group D Strep

Bile esculin positive

36

Bile esculin reaction of Enterococcus

Bile esculin positive

37

PYR reaction of Enterococcus

PYR positive

38

True/False. Enterococcus grows in lower NaCl concentration

False. Enterococcus thrives in higher NaCl concentration

39

Enumerate the α-hemolytic streptococci

- S. pneumoniae
- Viridans group streptococci
- Nutritionally variant streptococci
- Sometimes enterococcal species

40

Lancefield group of S. pneumoniae

No Lancefield group

41

True/False. S. pneumoniae infects humans and animals

False. S. pneumoniae infects humans EXCLUSIVELY, it has no reservoir in nature

42

Most significant disease caused by S. pneumoniae

Pneumococcal pneumonia

43

Microscopic appearance of S. pneumoniae

Gram-positive cocci in pairs
Lancet-shaped

44

Colony morphology of S. pneumoniae

Round
Usually wet, glistening, mucoid

45

Type of hemolysis exhibited by S. pneumoniae

α-hemolysis

46

Optochin susceptibility of S. pneumoniae

Optochin susceptible

47

Bile solubility of S. pneumoniae

Bile soluble

48

Viridans strep is normal flora in the

Upper respiratory tract
Urogenital tract

49

Clinical significance of Viridans strep

Subacute bacterial endocarditis

50

Type of hemolysis of Viridans strep

α-hemolysis

51

Optochin susceptibility of Viridans strep

Optochin resistant

52

Enumerate the Viridans strep

S. mutans
S. anginosus
S. gallolyticus (bovis)
S. salivarius

53

Microscopic characteristics of the family Streptococcaceae

Gram-positive cocci in chains or pairs