Gram (+) Cocci

Question 1

This Gram + cocci is catalase positive and coagulase positive

Answer 1

S. aureus

Question 2

This Gram + cocci is catalase positive, coagulase negative, and sensitive to Novobiocin

Answer 2

S. epidermidis

Question 3

This Gram + cocci is catalase positive, coagulase negative, and resistant to Novobiocin

Answer 3

S. saprophyticus

Question 4

What diseases does S. aureus cause?

Answer 4

CUTANEOUS: impetigo, folliculitis, carbuncle
DISSEMINATED: osteomyelitis, septic shock, pneumonia
TOXIN MEDIATED: TSS -> TSST-1, scalded skin syndrome, food poisoning

Question 5

What diseases does S. epidermidis cause?

Answer 5

infections on foreign bodies (intravascular devices, catheters)

Question 6

What disease does S. saprophyticus cause?

Answer 6

UTI

Question 7

This Gram + cocci is catalase negative, alpha-hemolytic, and sensitive to Optochin

Answer 7

S. pneumoniae

Question 8

What diseases does S. pneumoniae cause?

Answer 8

pneumonia, otitis media, endocarditis, meningitis, sinusitis, bacteremia

Question 9

This Gram + cocci is catalase negative, alpha-hemolytic, and resistant to Optochin

Answer 9

Viridans streptococcus (S. mutans and S. sanguis)

Question 10

What diseases do Viridans Strep cause?

Answer 10

S. mutans: dental caries

S. sanguis: endocarditis

Question 11

This Gram + cocci is catalase negative, beta-hemolytic, and bactracin sensitive

Answer 11

S. pyogenes

Question 12

What diseases does S. pyogenes cause?

Answer 12

PYOGENIC: pharygntiis, eryspelas, cellulitis, impetigo
TOXIGENIC: scarlet fever, toxic shock, necrotising fasciitis
IMMUNOGENIC: rheumatic fever, glomerulonephritis

Question 13

This Gram + cocci is catalase negative, beta-hemolytic, and bacitracin resistant

Answer 13

S. agalactiae

Question 14

What disease does S. agalactiae cause?

Answer 14

neonatal disease

Question 15

This Gram + cocci is catalase negative and gamma hemolytic

Answer 15

Enterococci

Question 16

What diseases does Enterococci cause?

Answer 16

bacteremia, intra-abdominal abscess, UTI, endocarditis, peritonitis

Question 17

Which two Gram + cocci are lancet shaped?

Answer 17

S. pneumoniae and Enterococci

Question 18

S. pneumoniae is bile ___, while Viridans Strep is bile ____

Answer 18

soluble; insoluble

Question 19

The PRY test is positive (red) for which Gram + cocci

Answer 19

S. pyogenes

Question 20

S. aureus turns a tellurite agar ____ while S. epidermidis turns a tellurite agar _____

Answer 20

black; gray