Deck 14: Streptococcus, Enterococcus, and Similar Organisms

Question 1

What name is given to the type of hemolysis that produces complete hemolysis and a clearing of the medium?

A)Beta hemolysis
B)Gamma hemolysis
C)Alpha hemolysis
D)Kappa hemolysis

Answer 1

A
Beta hemolysins cause complete hemolysis of erythrocytes, making blood agar appear clear around the colony.

Question 2

Streptococcus pneumoniae can be described as

A)susceptible to bile and optochin.
B)alpha hemolytic.
C)a major cause of bacterial meningitis.
D)often carrying an antiphagocytic capsule.
E)All of the above are true.

Answer 2

E
All statements are True regarding Streptococcus pneumoniae.

Question 3

The bacterial species that can be described as susceptible to bile and optochin, alpha hemolytic, a major cause of bacterial meningitis, and often carrying an antiphagocytic capsule is

A)Enterococcus faecalis.
B)Streptococcus pneumoniae.
C)Streptococcus pyogenes.
D)Streptococcus agalactiae.
E)viridans streptococci.

Answer 3

B
All descriptions given are typical of Streptococcus pneumoniae.

Question 4

Erythrogenic toxin, hyaluronidase, and hemolysins S and O are extracellular products of

A)Enterococcus faecalis.
B)Streptococcus pneumoniae.
C)Streptococcus pyogenes.
D)Streptococcus agalactiae.
E)viridans streptococci.

Question 5

The bacterial species that can be described as able to grow in 6.5% NaCl and 40% bile, part of the normal fecal flora of animals and humans, usually nonhemolytic, and a major cause of nosocomial infections is

A)Enterococcus faecalis.
B)Streptococcus pneumoniae.
C)Streptococcus pyogenes.
D)Streptococcus agalactiae.
E)viridans streptococci.

Question 6

Differentiation of the pleomorphic strains of streptococci and the similar corynebacteria or lactobacilli can be best accomplished by

A)examination of Gram stain of colony.
B)vancomycin susceptibility testing.
C)serologic testing.
D)examination of morphology following growth in thioglycollate broth.

Question 7

Enterococci can be described as

A)able to grow in 6.5% NaCl.
B)usually alpha hemolytic.
C)a major cause of pharyngitis.
D)often carrying an antiphagocytic capsule.
E)All of the above are true.

Question 8

Choose the genus that is best described as a catalase-negative, gram-positive coccus that is a facultative anaerobe and that forms chains.

A)Streptococcus
B)Stomatococcus
C)Staphylococcus
D)Micrococcaceae

Question 9

Generally speaking, nutritionally variant streptococci require what ingredient not found in most conventional media?

A)Vitamin B6.
B)Nalidixic acid and its components
C)NAD enrichment
D)Blood or blood products

Question 10

Streptococcus agalactiae can be described as

A)able to hydrolyze hippurate.
B)alpha hemolytic.
C)a major cause of.pharyngitis.
D)often carrying an antiphagocytic capsule.
E)All of the above are true.

Question 11

The bacterial species that can be described as able to hydrolyze hippurate, beta hemolytic, a major cause of neonatal meningitis and sepsis, and producer of the CAMP factor is

A)Enterococcus faecalis.
B)Streptococcus pneumoniae.
C)Streptococcus pyogenes.
D)Streptococcus agalactiae.
E)viridans streptococci.

Question 12

CAMP factor is produced by

A)Enterococcus faecalis.
B)Streptococcus pneumoniae.
C)Streptococcus pyogenes.
D)Streptococcus agalactiae.
E)viridans streptococci.

Question 13

The major etiologic agent of bacterial endocarditis in the United States is

A)Enterococcus faecalis.
B)Streptococcus pneumoniae.
C)Streptococcus pyogenes.
D)Streptococcus agalactiae.
E)viridans streptococci.

Question 14

What name is given to the type of hemolysis that produces incomplete hemolysis and a greening discoloration of the medium?

A)Beta hemolysis
B)Gamma hemolysis
C)Alpha hemolysis
D)Kappa hemolysis

Question 15

The bacterial species that can be described as susceptible to penicillin and bacitracin, beta hemolytic, a major cause of bacterial pharyngitis, and often carrying an antiphagocytic M protein is

A)Enterococcus faecalis.
B)Streptococcus pneumoniae.
C)Streptococcus pyogenes.
D)Streptococcus agalactiae.
E)viridans streptococci.

Question 16

Not only normal flora of humans and animals, this genus of bacteria contains agents of important diseases such as rheumatic fever, glomerulonephritis, and exudative pharyngitis.

A)Staphylococcus
B)Streptococcus
C)Enterococcus
D)Micrococcus

Question 17

What morphologic feature is a major consideration in determining an identification scheme for streptococci?

A)Colony shape and color
B)Hemolytic pattern
C)Smell
D)Consistency

Question 18

Nutritionally variant streptococci (Abiotrophia)

A)require vitamin B6 for growth.
B)will grow on 5% sheep blood agar.
C)form satelliting colonies around Haemophilus species.
D)require vitamin K for growth.

Question 19

Development of glomerulonephritis is a problem that may be encountered by patients infected with

A)Enterococcus faecalis.
B)Streptococcus pneumoniae.
C)Streptococcus pyogenes.
D)Streptococcus agalactiae.
E)viridans streptococci.

Question 20

Development of acute rheumatic fever and subsequent valvular heart disease are problems that may be encountered by patients infected with

A)Enterococcus faecalis.
B)Streptococcus pneumoniae.
C)Streptococcus pyogenes.
D)Streptococcus agalactiae.
E)viridans streptococci.

Question 21

Optochin, PYR, bile solubility, esculin, and 6.5% NaCl are tests most likely performed on a/an

A)alpha-hemolytic streptococcus.
B)beta-hemolytic streptococcus.
C)nonhemolytic streptococcus.
D)All of the above are correct.

Question 22

A vancomycin-resistant cocci is likely not

A)Pediococcus.
B)Leuconostocs.
C)streptococci.
D)lactobacilli.

Question 23

The drug of choice for most streptococcal infections is

A)vancomycin.
B)streptomycin.
C)penicillin.
D)Septra.

Question 24

Bacitracin, PYR, CAMP and hippurate are tests most likely performed on a/an

A)alpha-hemolytic streptococcus.
B)beta-hemolytic streptococcus.
C)nonhemolytic streptococcus.
D)All of the above are correct.

Question 25

The drug of choice for most enterococcal infections is

A)vancomycin and a penicillin.
B)clindamycin and vancomycin.
C)a penicillin and an aminoglycoside.
D)Septra.

Question 26

The rapid antigen detection methods for throat swabs used for screening patients for streptococcal pharyngitis

A)can be useful in quickly identifying most cases of streptococcal pharyngitis.
B)is a quick way to rule out streptococcal pharyngitis and avoid giving antibiotics when not needed.
C)are always very sensitive and specific for streptococcal pharyngitis.
D)are a quick and accurate way to diagnose bacterial and viral pharyngitis.