Rapid ID and Automation

Question 1

E. coli rapid ID BAP, s/, MAC

Answer 1

BAP: BH
MAC: LF
s/ gnb
Oxidase: NEG
Spot indole: POS

Question 2

Purpose of CMBCS?

Answer 2

Speeds recovery of organisms from a blood culture by gentle agitation of bottles AND constant readings of any changes in the bottle that occur due to metabolic activity by organisms

Question 3

Rationale for rapid ID (2 reasons)

Answer 3

1. Identify specific microorganisms to genus (sometimes species level) w/ >=95% accuracy
2. Rule out potentially serious pathogens within stated limitations

Question 4

Type of reaction used for ID?

Often fluorometric, measures rate of decrease in (fluorescent) signal

Answer 4

Reaction rate

Question 5

What does the acronym MALDI-TOF-MS mean?

Answer 5

Matrix-assisted laser desorption/ionization time of flight mass spectrometry

Question 6

What is TFA and its function?

Answer 6

Trifluoroacetic acid

Solvent used for cleaning reusable MALDI target plates (handle only in fume hood)

Question 7

% Accuracy possible with rapid ID

Answer 7

> = 95%

Question 8

Type of reaction used for ID?

pH generated by metabolic activity decreases a fluorescent signal

Answer 8

Quenching

Question 9

Proteus rapid ID?

Answer 9

BAP: NH swarmer
MAC: NLF
Oxidase NEG
Indole: NEG

Question 10

What does CMBCS stand for?

Answer 10

Continuous monitoring blood culture systems

Question 11

Type of reaction used for ID?

Fluorescence is generated (increased fluorescent signal) when substrate-fluorochrome bond is cleaved by enzyme

Answer 11

Fluorogenic

Question 12

Type of reaction used for ID?

Fermentation, decarboxylation, simple substrate, urea and chromogenic agar

Answer 12

Traditional

Question 13

Type of reaction used for ID?

Detects flow of electrons using redox dye

Answer 13

Carbon-source oxidation

Question 14

In MALDI-TOF, the ions’ TOF is analyzed to calculate what value?

Answer 14

m/z (mass-to-charge) ratio