Helicobacter Flashcards Preview

RUSVM Bacteriology Gram Negatives > Helicobacter > Flashcards

Flashcards in Helicobacter Deck (41):
1

Helicobacter Gram___? Shape?

Gram negative Spiral-shaped or curved

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2

Helicobacter Motile/Non-motile?

Flagellated, Motile

3

Helicobacter- Original classification

Originally Campylobacter

4

Helicobacter- Associated with what signs in all species?

GI tract disease

5

Helicobacter pylori Human disease pattern

Persistent gastritis Peptic ulcer disease Gastric adenocarcinoma (?) Gastric mucosal-associated lymphoma (?)

6

Helicobacter Disease range in animals

Asymptomatic to Gastritis to Cancer

7

Helicobacter Virulence Factors Name them

Flagella Urease Adhesins LPS CagPAI Vac CDT

8

Helicobacter Virulence Flagella

Motility for penetration of mucus Adherence to gastric epithelia

9

Helicobacter Virulence Urease

Hydrolyzes urea to ammonium **Ammonium neutralizes gastric acids** Associated with inflammation

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10

Helicobacter Virulence Adhesins

"Saba and Baba" SabA- Sialic acid-binding adhesin BabA - Blood group antigen-binding adhesin

11

Helicobacter Virulence LPS

Usual Endotoxin, pro-inflammatory cytokines, O-repeats=anticomplement

12

Helicobacter Virulence Cag PAI Codes for what?

Cytotoxin associated gene pathogenicity island Codes for T4SS Allows CagA protein into host cells

13

Helicobacter Virulence Vac

Vacuolating Cytotoxin -Disrupts epithelial barrier -Pro-inflammatory

14

Helicobacter Virulence CDT

Cytolethal Distending Toxin -Similar to that from C. jejuni

15

Helicobacter - Culture conditions Aerobe/Non-aerobe

Microaerophilic (Not aerobic)

16

Helicobacter - Culture conditions Optimal growth temp

37C

17

Helicobacter - Culture Colony description

Slow-growing, flat, non-pigmented, non-hemolytic colonies.

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18

Helicobacter - Culture conditions Fastidious?

Yes! Needs selective media

19

Helicobacter - Culture conditions - Selective media

Vancomycin Amphotericin Trimethoprim Cefsulodin Lysed horse blood

20

Helicobacter Reservoir

**Gastric mucus layer** Many animals

21

What percentage of dogs and cats are infected with Helicobacter spp?

80-100%

22

How many slaughtered pigs are infected with Helicobacter suis?

60%

23

Helicobacter Transmission

Oral-oral Fecal-oral

24

Helicobacter Zoonotic potential

Some evidence, not huge risk

25

Helicobacter Pathogenesis

Not perfectly understood -Alters GI physiology w/Urease -Adjusts to gastric environment & colonizes -Chronic inflammation

26

Helicobacter Pathological changes

Gastric & Hepatic

27

Helicobacter - Pathology of Stomach

Hyperplasia Reduction of mucus Degeneration of glands Necrosis Variable inflammation

28

Helicobacter -Pathology of liver

Inflammatory and necrotizing lesions

29

Helicobacter - Lab Dx Smears/Stains

Of gastric mucosa Difficult/not impossible to identify this way

30

Helicobacter- Lab diagnostic methods

Stained gastric mucosa smears Urease tests Culture is difficult PCR/Western Blot/ FISH

31

What is the FISH diagnostic test?

Fluorescence in situ hybridization

32

Helicobacter Treatment theory

Controversial, most infections subclinical -Resistance could develop quickly

33

Helicobacter Treatment drugs

Combination therapies effective: Amoxicillin & Metronidazole Amoxicillin & clarithromycin Bismuth subsalicylate, omeprazole &/or famotidine for clinical gastric infections

34

H. pylori

Catalase Pos/Neg?

 

Catalase Positive

35

H. pylori

Oxidase Pos/Neg?

Oxidase Positive

36

H. pylori

Alkaline Phosphatase pos/neg?

Alkaline Phosphatase Positive

37

H. pylori

Indoxyl acetate pos/neg?

Indoxyl acetate Negative

38

H. pylori

Growth at 42 C?

No growth at 42 C

39

H. pylori

Growth in 1% glycine?

No growth in 1% glycine

40

H. pylori

Nitrate reductase pos/neg?

Nitrate reductase negative

41

H. pylori

Urease Pos/Neg?

Urease positive