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Flashcards in Rickettsiales Deck (61)
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1
Q

Rickettsiales description

A

Family Anaplasmataceae & Family Rickettsiaceae - Obligate intracellular gram negative bacteria -

2
Q

Family Anaplasmataceae

A

Anaplasma - Ehrilichia - Neorickettsia

3
Q

Anaplasma spp

A

Survive in cytoplasmic vacuoles of erythrocytes, phagocytes, platelets & myeloid cells

4
Q

Ehrlichia spp.

A

Survive in phagocytic cells

5
Q

Neorickettsia spp

A

Survive in macrophages & mononuclear cells

6
Q

Family Rickettsiaceae

A

Rickettsiae spp: R. rickettsia, wolbackia, oreintia

7
Q

Rickettsiae spp

A

Survive in vascular endothelium

8
Q

Anaplasma spp description

A

Gram negative, small coccoid-ellipsoid

9
Q

Anaplasma spp list

A

A. marginale, centrale, ovis, bovis, platys, phagocytophilum

10
Q

A. marginale

A

REPORTABLE, transmission with hard ticks (Ixodes), infects ruminants - Bovine anaplasmosis

11
Q

Bovine anaplasmosis

A

A. marginale - undulating febrile disease - Long-term carriage.

12
Q

When I say Bovine anaplasmosis, you say,

A

Anaplasma marginale!

13
Q

A. marginale pathogenesis in bovine

A

Bovine anaplasmosis! Erythrocytes engulf bacteria–> multiplication & release of new –> indiscriminate erythrocyte removal by host’s macrophage system–> anemia, icterus, splenomegaly, hepatomegaly –> DESTRUCTION OF RBC!!

14
Q

Anaplasma platys

A

Infectious canine cyclic thrombocytopenia - Cycles of 1-2 week interval -

15
Q

Tick species that transmit Anaplasma platys

A

Rhiphicephalus & Dermacentor

16
Q

Anaplasma phagocytophilum

A

Tick borne fever in ruminants, human, equine - Canine granulocytic anaplasmosis - Transmitted by rodents & ixodes (hard ticks)

17
Q

What species causes canine granulocytic anaplasmosis?

A

A. phagocytophilum

18
Q

What species causes Infectious canine cyclic thrombocytopenia?

A

A. platys

19
Q

Rickettsiae - description

A

Small, gram negative, nonmotile (but hijacks actin in cells)

20
Q

Rickettsiae pathogenesis

A

Enter endothelials –> escape phagosome & multiply in cytoplasm & nucleus

21
Q

What disease is caused by Rickettsia rickettsia?

A

Rocky Mountain Spotted Fever

22
Q

What causes Rocky Mountain Spotted Fever?

A

Rickettsia rickettsia

23
Q

What does Rickettsia felis cause?

A

Typhus group

24
Q

What disease does Coxiella burnetii cause?

A

Q fever

25
Q

What causes Q fever?

A

Coxiella burnetii

26
Q

Rocky Mountain Spotted fever - Reservoir

A

Dogs & people, small mammals

27
Q

Rocky Mountain Spotted fever transmission

A

Dermecentor (Wood tick, American dog tick) (also transovarial & transtadial)

28
Q

Rickettsia ricketsii - Pathogenesis

A

In tick: replicate in epithelium–> to salivary glands & ovarian tissues - In vertebrate: Tick injects bacteria–> bacteria to endothelium, damage cell membrane –> vasculitis & thrombosis

29
Q

Rocky Mountain Spotted fever pathology

A

Rickettsia ricketsii - Severe necrosis in extremities, severe fatal disease (from vasculitis & thrombosis)

30
Q

Rocky Mountain Spotted fever DDx

A

Ehrlichiosis - Babesiosis - Baorreliosis

31
Q

Rocky Mountain Spotted fever prevention

A

Tick control, Tx with chloramphenicol, fluroquinolones, tetracyclines

32
Q

Coxiella burnetii General info

A

Survives in environment - have endospore-like growth phase - Can disseminate airborne - Bioweapon!! REPORTABLE

33
Q

Coxiella burnetii Hosts

A

Ticks, mites, lice, fleas ; Mammals

34
Q

Coxiella burnetii in humans

A

Q fever! subclinical influenza-like occupational disease - Endocarditis in chronic presentations

35
Q

Coxiella burnetii pathogenesis

A

inhalation/ingestion/arthropod bite –> vascular endothelium/renal & respiratory epithelia –> multiplies within phagosome - Persistent in lactating mammary gland and pregnant uterus

36
Q

Ehrlichiae general

A

WBC obligate intracellular bacteria - multiply within membrane lined intracytoplasmic vesicles

37
Q

Ehrlichiae genus

A

Ehrlichia & Neorickettsia - Tick transmitted species - Transtadially not transovarially

38
Q

Ehrlichiae spp Tx

A

Tetracyclines, imodocarb dipropionate - Doxy & steroid for late-stage, poor prognosis

39
Q

Ehrlichia canis Dz & transmission

A

Canine monocytic ehrlichiosis - Transmitted by Rhiphicephalus (brown dog tick)

40
Q

Ehrlichia canis pathogenesis

A

Inoculation by tick bite–> incubation –> severe acute dz develops, progresses to chronic (tropical canine pancytopenia) - Thrombocytopenia, leukopenia, anemia, secondary infections

41
Q

E. chaffensis

A

Human monocytic ehrlichiosis - Dermacentor (american dog tick) - Deer=reservoir

42
Q

What is the species of tick that transmits E. chaffensis

A

Dermacentor (American dog tick)

43
Q

E. ewingii

A

Canine granulocytic ehrlichiosis - Transmitted by Ambylomma americanum (Lone Star Tick)

44
Q

E. ruminantium

A

Africal heartwater - REPORTABLE - Ruminants in africa & caribbean - Some cattle breeds resistant

45
Q

E. ruminantium transmission

A

Amblyomma vector - parenteral introduction to blood

46
Q

E. ruminantium pathogenesis

A

Inoculation–> multiplication in reticuloendothelial cells lining lymph node sinusoids–> vascular dissemination & endothelial colonization –> vasculitis, pericardial effusion

47
Q

E. ruminatium Signs

A

Fever, followed by neurological signs (collapse & convulsions)

48
Q

Neorickettsia description

A

Small, non-motile, coccoid, intracytoplasmic vacuoles - In monocytes, macrophages, enterocyte - Vectors=Flukes

49
Q

Neorickettsia helminthoeca diseases

A

Salmon poisoning disease - Elokomin fluke fever (mild form)

50
Q

Neorickettsia helminthoeca - Pathogenesis

A

Dog ingests fluke-contaminated fish (encysted in salmon–> attachment & penetration of duodenal mucosa by trematode –> hemorrhagic enteritis w/bacterial spread to lymph node, spleen, liver, lungs, brain, thymus

51
Q

Neorickettsia helminthoeca - Life with the helminth

A

N. helminthoeca maintained by transovarial passage in the helminth, found throughout life cycle of the fluke - Only obligatory helminth borne pathogenic bacteria!

52
Q

Neorickettsia helminthoeca target cells

A

Canine mononuclear cells

53
Q

Neorickettsia helminthoeca Dx

A

Location, detection of fluke eggs, history of dog health

54
Q

Neorickettsia helminthoeca Prevention

A

Don’t let dogs eat raw fish!

55
Q

Neorickettsia risticii

A

Potomac Horse Fever! - Equine monocytic ehrlichiosis - Equine sours

56
Q

When I say equine sours, you say

A

Neorickettsia risticii

57
Q

When I say Potomac horse fever, you say…

A

Neorickettsia risticii

58
Q

Neorickettsia risticii Target cells

A

Affinity for blood monocytes, tissue macrophages, intestinal epithelial cells

59
Q

Neorickettsia risticii - Reservoir

A

Infectious life cycle involves intermediate snail reservoir & trematode cercaria (proximity to bodies of water, summertime)

60
Q

Neorickettsia risticii clinical signs

A

Diarrhea

61
Q

Aegyptianellosis

A

Aegyptianella pullorum - Poultry & wild birds - Tick: Argus! - Lesions: hepatosplenomegaly, punctiform hemorrhages on serosal surfaces