Week 2: Skin and Soft Tissue Infections (2)

Question 1

What type of organism is Staph Aureus?

How can we distinguish it from the other similar organisms?

Answer 1

Gram positive cocci

Growth in air: Yes
Catalase: +ve (bubbles)
Coagulase: +ve

Question 2

What type of organism is Strep Pyogenes (Grp. A)?

How can we distinguish it from other similar organisms?

Answer 2

Gram positive cocci

Growth in air- Yes
Catalase:-ve
B haemolysis, no growth on Mac
Bacatracin sensitive

Question 3

What kind of organism is pseudomonas aureginosa?

How can we distinguish it?

Answer 3

Gram negative rods (loves water)

Growth in air/CO2: Yes
Growth on NA/MAC: Yes
Oxidase: Positive
‘O’ test

Question 4

What kind of organism is candidia albicans?

What do we use to grow it?

Answer 4

Yeast (large purple cells)

CHROMagar Candidia (aqua growth)

Question 5

What kind of organism is Varicella Zoster?

How can we test for it?

Answer 5

PCR for VZV