Lecture 8 C - Legionella pneumoPHILA (Dr. Daniels)

Question 1

Where was Legionella pneumoPHILA found?

Answer 1

PHILAdelphia

Question 2

What disease is caused by Legionella pneumophila?

Answer 2

Legionnaire’s disease

Question 3

Gram +/-?

Answer 3

Gram -

Question 4

Describe L. pneumophila

Answer 4

gram negative
pleomorphic (many shapes)
obligate aerobe (needs oxygen)
needs CYSTEINE

Question 5

ENCOUNTER

Answer 5

contaminated water

Question 6

What is L. pneumophila is a ______ of protozoa

Answer 6

parasite

Question 7

What kind of temp does it like?

Answer 7

thermotolerant (up to 46 degrees C)

Question 8

Encountered through…

Answer 8

environmental aerosols

NOT person-to-person

Question 9

Multiply/Spread

Answer 9

• phagocytosed in alveoli
• multiply w/in autophagosomes of phagocytic immune cells (alveolar macrophages)
• inflammation –> acute bronchopneumonia

Question 10

Damage/Immune Response

Answer 10

1. Cell mediated immune response

2. Virulence/Proinflammatory mechanisms

Question 11

What occurs w/ cell mediated immune response to L. pneumophila?

Answer 11

secrete IFN-gamme (sequester Iron)

Question 12

What are some proinflammatory/virulent mechanisms of L. pneumophila?

Answer 12

1. survives in macrophages
2. LPS has cytotoxic effects
3. FLAGELLIN

Question 13

What does Flagellin do?

Answer 13

It is recognized by TLR-5 receptors on innate immune system cells and therefore inhances inflammation.

Question 14

How do we treat Legionaire’s disease?

Answer 14

Antimicrobial drugs with good INTRACELLUAR PENETRATION.

• macrolides
  - fluoroquinolones
  - tetracyclines

Question 15

Can penicillin treat legionnaire’s disease?

Answer 15

No. it is polar, so it can’t cross the cell membrane well enough.

Question 16

Which medications are used to treat legionnaire’s disease?

Answer 16

Macrolides
Fluoroquinolones
Tetracyclines