Legionella

Question 0

Which is false about Legionella?
A. Oxidase (-)
B. Catalase (+)
C. Motile

Answer 0

A

Question 1

False about Legionella
A.stains poorly with gram stain B.Facultative intracellular pathogen
C.Grows best in warm water sources D.Transmitted via person to person contact

Answer 1

D

Contaminated aerosols dapat

Question 2

Specialized media for Legionella

Answer 2

Buffered Charcoal Yeast Extract agar

Question 3

In lab diagnosis of Legionella, seroconversion must be seen. What is seroconversion?

Answer 3

4 fold or greater rise in specific serum antibody titer L. pneumophila

Question 4

Where was Legionnaire’s disease first discovered?

Answer 4

American Legion Convention.

Question 5

How is L.pneumophila transmitted?

Answer 5

Contaminated aerosol droplets

Question 6

To create biofilms, what does L.pneumophila secrete?

Answer 6

Alginate

Question 7

Identify the clinical manifestation:

• Incubation period: 1-2 days
• flu-like; fever, headache, malaise
• milder than Legionnaire’s (no mortality)
• self-limiting

Answer 7

Pontiac fever

Question 8

Sequence the Steps in pathogenesis:
A.Lysis of the phagosome leads to apoptosis and release of the organism B.Phagocytosis into the monocytes by binding to complement receptors
C.Replication within the phagosome
D.Inhibition of phagolysosome fusion (phagosome+lysosome)

Answer 8

B D C A

Question 9

Which is not an effective prevention measure for Legionella?
A,Regularly maintain and clean cooling towers and evaporative condensers
B.Maintain domestic water heaters at 40°C
C. Avoid conditions that allow water to stagnate.
D. Frequent flushing of unused water lines

Answer 9

B.

60 degrees dapat

Question 10

In staining Legionella, what must be used instead of safranin?

Answer 10

Basic fuchsin (0.1%)

Question 11

Does person to person transmission of Legionella occur?

Answer 11

No

Question 12

True about Legionella
A. Produces gelatinase
B. Does not hydrolyze hippurate
C. Does not produce beta-lactamase

Answer 12

A

Question 13

Major outer membrane protein inhibits __

Answer 13

Acidifiation of phagolysosome

Question 14

Macrophage infectivity/invasion potentiator is required for ___

Answer 14

Optimal internalization, determines cell entry

Question 15

What is coiling phagocytosis?

Answer 15

Bacteria replicates inside vacuole, recruits RER & prevents phagolysosome fusion

Question 16

Legionella grow slowly, yes or no?

Answer 16

Yes

Esp in blood culture: at least 2 wks

Question 17

When are serologic tests most useful in detecting Legionella?

Answer 17

Retrospective diagnosis @ outbreaks

Question 18

False about L.micdadei
A.acid-fast in tissues
B.able to hydrolyze hippurate
C.absence of beta-lactamase
D.pneumonia causing usually in immunocompromised

Answer 18

B