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RUSVM Bacteriology Gram Negatives > Yersinia > Flashcards

Flashcards in Yersinia Deck (33)
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1
Q

Yersinia description

A

Gram negative, lactose negative, bipolar staining in smears, most motile (except Y. pestis)

2
Q

Yersinia Important species

A

Y. ruckeri (fish) - enterocolitica (domestics & primates) - pseudotuberculosis (birds,rodents, domestics, primates) - **Y. pestis (Plague! zoonosis, rodents, cats)

3
Q

Yersinia pestis - Most known as

A

The bubonic plague! Bioweapon - Rodent based zoonotic disease

4
Q

Yersinia pestis Presentations

A

Local lymphadenitis (bubonic plague) - Pneumonia (pneumonic plague, 50% fatal) - Septicemia (septicemic plague, fatal if untreated)

5
Q

Yersinia pestis virulence factors

A

Incomplete LPS (no O-Ag) - Pla - Hms - Yops & LcrV - Ymt - Gsr

6
Q

Pla

A

enhace visceral colonization, bacterial metastasis

7
Q

Hms

A

Iron acquisition, colonization of flea proventriculus***

8
Q

Yops & Lcrv

A

Effector proteins act as toxins

9
Q

Ymt

A

protects bacteria from digestive enzymes in flea

10
Q

Gsr

A

Survival of bacteria in phagolysosome in macrophages

11
Q

Yersinia pestis reservoir

A

Rodents! Endemic areas: intermediate hosts- squirrels, prairie dogs, rats, rabbits

12
Q

Yersinia pestis Transmission

A

Fleas, airborne, oral

13
Q

Yersinia pestis pathogenesis

A

First intracellular, then extracellular* Fleas feed–> bacteria blocks proventriculus & contaminates feeding site –> bacteria killed at sige by PMNs & inflammation –> some survive in macrophages–> induce apoptosis–> secrete proteins –> further survival–> extracellular survival

14
Q

Yersinia pestis in humans

A

Traced to feline infection - 15% fatality with treatment - Inoculation via cuts, bites, scratches, airborne, flea borne, ingestion of infected meat or necropsy exposure

15
Q

Yersinia pestis in cats

A

Ingest infected prey - Regional lymphadenitis - Symptomatic cases are fatal - Cat & dog flease (Ctenocephalides) doesn’t transmit bacteria (no proventricular blockage)

16
Q

Yersinia pestis Culture

A

Blood or chocolate agar, stain with Wayson’s or gram stain

17
Q

Yersinia pestis treatment

A

Report suspected feline plague!! (isolate, treat for fleas) no vaccines

18
Q

Yersinia pseudotuberculosis

A

Worldwide - cold months - Birds & rodents, occasionally cats

19
Q

Yersinia pseudotuberculosis in birds & rodents

A

Mesenteric lymphadenitis - terminal ileitis - acute gastroenteritis - septicemia

20
Q

Yersinia pseudotuberculosis virulence factors

A

Ail - Inv * Yad - Very similar to Y. pestis

21
Q

Yersinia pseudotuberculosis Ail

A

Adhere M cells, protects from complement

22
Q

Yersinia pseudotuberculosis Inv & Yad

A

Adherence to M cells & basolateral ileal epithelial cells - Yad protects from complemen

23
Q

Yersinia pseudotuberculosis pathogenesis

A

Similar to pestis - Intracellular then Extracellular

24
Q

Yersinia pseudotuberculosis disease patterns

A

Diarrhea (PMN recruitment & PG release) - Septicemia (immune system exhausted during local phase) - Necrosis of intestinal wall, abdominal lymph nodes, visceral organs

25
Q

Yersinia pseudotuberculosis immunity

A

Natural infection leads to immunity - Avirulent live vaccines are protective but not available - Responds to same antimicrobials as Y. pestis

26
Q

Yersinia enterocolitica species affected & disease pattern

A

Domestics & primates - Mesenteric lymphadenitis, terminal ileitis, acute gastroenteritis, septicemia

27
Q

Yersinia enterocolitica virulence factors

A

Yst - Yersinia stable toxin - unique - Open Cl channels for secretion & diarrhea

28
Q

Yersinia enterocolitica variability

A

2 subspecies, >70 serotypes from O antigen, 6 biogroups based on enzymatic reactivity

29
Q

Yersinia enterocolitica pathogenesis

A

same as Y. pseudoTB - Addition of Yst induced diarrhea (more adapted to extracellular existence) - Most infections are self-limiting

30
Q

Yersinia enterocolitica fastidious-ness

A

Requires cold enrichment - special culture media

31
Q

Yersinia enterocolitica treatment

A

Fluoroquinolones, tetracycline etc (resistant plasmids to tetracycline & streptomycin are common)

32
Q

Yersinia ruckeria

A

“Enteric redmouth - Rainbow trout - Hemorrhagic inflammation of perioral area - mortalities in hatcheries - Outbreaks controled with sulfonamides, tetracyclin etc. - Some sulfa bacterin vaccine help

33
Q

If I say enteric redmouth of trout, you say…

A

Yersinia ruckeria