Species Identification

Question 1

Gram positive cocci in clusters, catalase positive

Answer 1

Staphylococcus

Question 2

Gram positive cocci in chains/pairs, catalase negative

Answer 2

Streptococcus or enterococcus

Question 3

Gram positive bacilli in “chinese letters” appearance, catalase and coagulase positive, reverse positive CAMP test

Answer 3

Corynebacterium spp.

Question 4

Gram positive bacilli, highly catalase positive, coagulase positive, CAMP test positive

Answer 4

Listeria monocytogenes

Note: intrinsically resistant to cephalosporins!

Question 5

Gram positive cocci in clusters, catalase positive, coagulase double positive

Answer 5

Staphylococcus aureus

Question 6

Gram positive cocci in clusters, catalase positive, slide coagulase positive, tube coagulase negative

Answer 6

Staphylococcus lugdanensus

Question 7

Gram positive cocci in clusters, catalase positive, slide coagulase negative, tube coagulase positive

Answer 7

Staphylococcus pseudintermedius

Question 8

Gram positive cocci in clusters, catalase positive, coagulase double negative

Answer 8

Staphylococcus that is not aureus, lugdanensus, or pseudintermedius

Eg S saprophyticus (UTI)