Bacteriology Methods

Question 1

Optochin

Differentiates what organism? How?

Answer 1

aka P-Disk

Strep pneumoniae are SENSITIVE

Question 2

Oxidase positive GNRs (list 6)

Answer 2

Vibrio
Aeromonas
Neisseria
Pseudomonas
Campylobacter
Pasteurella

Question 3

List tests (4) which differentiated β hemolytic Strep

Answer 3

Bacitracin
•GAS SENS
•GBS RES

TMP-SXT
•GAS RES
•GBS RES

PYR
•GAS+

Hippurate
•GBS+

Question 4

List tests (3) to diff Group D Strep

Answer 4

Bile esculin
•GDE+
•S. bovis+

6.5 NaCl
•GDE RES
•S. bovis SENS

PYR
•GDE+
•S. bovis-

Question 5

DNAse

Answer 5

Distinguishes Moraxella catarrhalis from Neisseria

Question 6

Who needs X and V factors?

Answer 6

Haemophilus spp

Question 7

What is X and V factor?

Answer 7

V = NAD

X = hemin

Question 8

Superoxol test

Answer 8

30% H2O2

(Catalase is 3%)

N gonorrhea brisk bubbling

N meningitidis weak delayed bubbles

Question 9

Neisseria CHO use profiles

Answer 9

Glucose ==> gonorrhea
Maltose ==> meningitidis
Sucrose
Lactose ==> lactamica

Red ==> Yellow (acid)

Moraxella is negative for all

Question 10

What does the Staph streak test grow?

Answer 10

Haemophilus spp

Question 11

String test

Answer 11

V cholera vs non-cholera Vibrio

Question 12

Stuart’s broth

Christensens broth

Answer 12

Urease test

Rapid splitters = Proteus
Slow splitters = Klebsiella

Question 13

Who are PYR+?

Answer 13

GAS

GDE