Bacterial Infections of the Vascular System

Question 1

If you see morulae in phagocytic vacuoles think:

Answer 1

anaplasma or ehrlichia infection (both tx with docy)

Question 2

What is similar about: Rickettsia, Ehrlichia, and Anaplasma?

Answer 2

• small cocci-to-short-rods
• replicate within cells
• mamallian hosts
• arthropod vectors
• sensitive to tetracycline (doxycycline)

Question 3

What species is responsible for Q fever?

Answer 3

C. burnetti

Question 4

How is Q fever transmitted?

Answer 4

aerosols

Question 5

What cells do Q fever infect?

Answer 5

alveolar monocyte/ macrophages

Question 6

Name the virulence factors for Q fever:

Answer 6

phase I lipopolysaccharide = surface molecule –> immune evasion, after bacteria die–> toxic shock
acid phosphatase: inhibits resp. burst, allows survival in endosome

Question 7

Who can receive C. burnetti vaccines?

Answer 7

military

Question 8

What is the reservoir for R. rickettsia?

Answer 8

ticks, mice, wood animals

Question 9

What is the reservoir for R. conorii?

Answer 9

dog tick

Question 10

R. conorii causes _______

Answer 10

mediterranean spotted fever

Question 11

the reservoir for R. prowazekii is __________.

Answer 11

HUMANS (endemic typhus)

Question 12

What is the reservoir for scrub typhus/ O. tsutsugamushi?

Answer 12

rodents

Question 13

Ehrlichia reservoir

Answer 13

dogs, deer, mice

Question 14

Anaplasma reservoir

Answer 14

deer, mice

Question 15

What are the virulence factors of R. rickettsia?

Answer 15

OmpA&B: surface proteins –> adherence to host cells
T4SS: type 4 secretion –> cell entry
Phospholipase A2: escape from endosome
ActA; polymerizes actin to enhance cell-cell spread

Question 16

What are the virulence factors of R. conorii?

Answer 16

adhesins –> bind host cells

phospholipase –> destroys tissue

Question 17

Reservoir for R. typhi?

Answer 17

cats, rats (murine typhus)

Question 18

What disease is caused by R. rickettsia?

Answer 18

RMSF

Question 19

What disease is caused by R. conorii?

Answer 19

mediterranean spotted fever

Question 20

What disease is caused by R. prowazekii?

Answer 20

epidemic typhus, brill-zinnser

Question 21

What disease is caused by R. typhi?

Answer 21

murine typhus

Question 22

What disease is caused by O. tsutsugamushi?

Answer 22

scrub typhus

Question 23

What disease is caused by C. burnetii?

Answer 23

Q fever

Question 24

What is the drug of choice for RMSP, mediterranean spotted fever, typhus, Q fever, ehrlichia, anaplasma?

Answer 24

Tetracyclines- Doxycycline
* cant use doxy on pregnant women so use chloramphenicol (Rickettsia) or fluoroquinolones (Q Fever, Ehrlichia, Anaplasma)

Question 25

how do Ehrlichia and anaplasma present

Answer 25

similar to spotted fever without the spots

Question 26

T/F: you should not treat children with doxy even if they have one of these “rickettsial” infections?

Answer 26

FALSE: although doxy can interfere with tooth development these diseases are serious enough that treatment is still warranted

Question 27

where does rickettsia divide

Answer 27

throughout the cell

Question 28

where do the “rickettsial” species replicate?

Answer 28

within infected cells - OBLIGATE INTRACELLULAR

Question 29

how can the “rickettsial” species by visualized?

Answer 29

All are difficult to stain chemically and require immunofluorescent assay to visualize