Intro Flashcards
What bacteria causes rocky mountain spotted fever?
Rickettsia rickettsii
What bacteria causes rickettsiapox?
R.Akari
What bacteria causes epidemic typhus?
Rickettsia Prowazekii
What baceria causes murine typhus?
Rickettsia Typhi
What bacteria causes scrub typhus?
Orientia Tsutsugamushi
What bacteria causes Ehrlichiosis
HME(human monocyte): E.Chaffeensis
HA(Human Anaplasmosis): A.Phagocytophlium, E.Ewingii
What bacteria causes Q fever?
Coxiella Burnetii
What are the general characteristics of these bacteria?
Obligate Intracellular
Transmitted by arthropods
clinical: fever, HA, rash
What are the morphology of these bacteria
Small Gram Neg Rods (Giemsa stain)
LPS/peptidoglycan missing in some
No flagella
Are these bacteria able to make their own ATP?
Yes
Early infection - use host
Later: use their own
What kind of stain can be used to visualize these bacteria?
Giemsa; Stain poorly with gram stain
Describe the pathogenesis of these bacteria?
Enter via endocytosis -> replicate in cytoplasmi vesicles or cytoplasm ->Exit via budding or lysis
Which bacteria replicate in cytoplasmic vesicles?
Phagosome: Ehrlichia, Anaplasma
Phagolysosome like vesicle: Coxiella
Which bacteria replicate in the cytoplasm?
Rickettsia
Orientia
How do ehrlichia and anaplasm avoid killing by lysosomes?
Prevent fusion of phagosome with lysosome
How does Coxiella prevent death from lysosomal fusion?
Prmotes delayed fusion with endosomes
Requires low pH for growth -> forms CCV (coxiella containing vesicle)
How do rickettsia and orientia replicate in the cytoplasm?
Escape vesicle using phospholipase A -> multiplay in cytoplasm -> migrate intracellularly using actin polymerization -> can use this to transfer between 1 cell to neighboring cell without exposure to immune system
Which ricketssia species does NOT use actin polymerization for migration intracellularly?
R.Prowazekii
What is unique about coxiella compared to rickettsia, orientia, ehrlichia anaplasma?
It can survive outside of the host as ti is resistant to drying
Rickettsia, orientia, ehrlichia, and anaplasm are unstable and die rapidly
Which disease are transmitted by ticks?
Rocky moutain spotted fever
Ehrlichiosis
Which disese are transmitted by mites?
Rickettsialpox
Scrub Typhus
Which disease are transmitted by lice?
Epidemic Typhus
Which disease are transmitted by fleas?
Murine Typhus
Which disease can be spread by aerosols from large mammals?
Q fever: Coxiella
What is the primary lesion due to bacterial infeciton and multiplicaiton with these species?
Rash -> vasculitis in many organs
How are diagnosis made for these bacteria?
Clinical findings + Epidemiologic information
Culturing is difficult and dangerous (obligate intracellular pathogens -> wont grow out in cultures in lab)
Serology: used to CONFIRM dx
IFA
MIF (microfluorescence assay)
PCR
How do we treat these infections?
Therapy before seroconversion - treat before dx confirmation
Tx: Tetracyclines and Chloramphenicol => bacteriostatic
DON’T USE SULFONAMIDES -> ENHACES DISEASE
Which diseases forms an eschar?
Rickettsialpox
Scrub Typhus
Whcih disease have a gradual onset of sx?
Epidemic Typhus
