Rickettsia/Bartonella Flashcards
Which kind of lice carry Rickettsia and Bartonella?
Body lice (not head lice)
Rickettsia stain poorly with ______________.
Gram staining, but they stain well with Giemsa
True or false: Weil-Felix media is needed to culture Rickettsia.
False. Weil-Felix agglutination tests are used to test for Rickettsia.
What do Rickettsia need from host cells?
NAD+, CoA, and cholesterol
Rickettsia typically invade _______________.
endothelial cells; they also spread hematogenously
Rickettsial typhus is caused by ________________.
Rickettsia prowazekii
What are the different rashes cause by R. rickettsii and R. prowazekii?
- R. rickettsii: starts on limbs and moves inward
* R. prowazekii: starts in center and moves outward
R. ricketsii is spread by the _____________ tick.
dermacentor
Give a rundown on Ehrlichia and Anaplasma.
- Obligate intracellular
- Infect phagocytes
- Multiply inside vacuoles
- Similar symptoms to Rickettsia but without rash (i.e., just headache, myalgia, and fever)
- Can cause leukopenia or thrombocytopenia
- Transmitted by ticks from deer and mice reservoirs
- Can cause raised AST/ALT
- Can cause inclusion bodies in leukocytes
- Treat with doxycycline
________________ are considered emerging diseases due to their increasing incidence, although some speculate that this is partly owing to better diagnostics.
Ehrlichiosis and Anaplasma
How are Ehrlichia and Anaplasma able to surviv inside endocytic vacuoles?
They downregulate oxygen radical generation.
Most ______________ infections are associated with eschars at the site of the bite.
Rickettsia
What’s the difference between epidemic typhus and Brill’s disease?
Both are caused by Rickettsia prowazekii, but Brill’s is milder and usually doesn’t present with a rash.
What is scrub typhus?
Caused by Orientia tsutsugamushi, scrub typhus presents like epidemic typhus (fever, pneumonia) but with an eschar at the site of the infection.
Most Rickettsial diseases occur during the __________.
summer
