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1

Describe the physical structure of Bacillus.

G+ Rods
Large, Fat, Square Ends
Chains, Palisades, Clumps

2

Bacillus response to adversity?

Sporulation

3

Oxygen metabolism of Bacillus.

Aerobic
Some species have butanediol or lactate ferm pathways.

4

Where can Bacillus be found primarily?

Soil and on Leaf Surfaces

5

Two types of Bacillus we covered?

Bacillus cereus
Bacillus anthracis

6

Bacillus cereus is typically seen in what context?

Food Poisoning

7

Describe the physical appearance of Bacillus cereus spores.

Subterminal

8

Describe the physical appearance of Bacillus cereus colonies on agar plates.

Large, flat, rough

9

What two varieties of Bacillus cereus are seen clinically?

Emetic Variety
Diarrheal Variety

10

Describe the clinical presentation of emetic variety Bacillus cereus.

Very Acute Onset (1-6 hrs)
Recovery in 12 hours
Nausea, Vomiting, Cramps

11

Describe the clinical presentation of the diarrheal variety of Bacillus cereus.

Slow onset (8-16 hrs)
Profuse Diarrhea, Cramps
No Vomiting

12

How do people get Bacillus cereus?

Cooked rice and pasta that has been cooled too slowly?

13

Why the fuck does it matter how slowly my rice cools?

Cooling slowly allows spores to germinate and produce the toxin

14

How many toxins are associated with Bacillus cereus?

4 (1 emetic toxin and three enterotoxins)

15

What does the emetic toxin of Bacillus cereus do?

K+ Ionophore

16

What are the three enterotoxins associated with Bacillus cereus?

Hemolytic
Non-hemolytic (pore-formers)
Cytotoxin (Activates Ad cyclase)

17

Unique physical characteristics of Bacillus anthracis?

Central Spores
"Cut glass" colonies on blood agar
Poly-D-glutamate capsule

18

Clinical presentation of Bacillus anthracis?

Papule (12-36 hrs) becomes a large necrotic eschar
Disseminates and becomes systemic
May infect any organ

19

What is an eschar?

a dry, dark scab or falling away of dead skin

20

Three most common causes of diarrhea (not necessarily in order)

Norovirus
S Aureus
B cereus

21

How is Bacillus anthracis typically contracted?

- Animals ingest/carry spores from soil
- Human handles infected animal materials
- Spore contacts mucous membranes or enter through abrasions
- Germinate in Macrophages after engulfment

22

How long are Bacillus anthracis spores viable?

more than 50 years

23

Four ways (even though they may kind of overlap..) that Bacillus anthracis can get into the body

Contact Mucus Membrane
Abrasion
Inhalation
Ingestion

24

Why should we give a shit about Bacillus anthracis if it comes up less than once a year in the whole world?

Possibly comes up in bioweaponization

25

What do spores do upon entering the host?

Enter macrophages
Germinate in the phagolysosome (upon O2 radical exposure)

26

Can Bacillus anthracis spores be found in blood smears?

No

27

Describe the Bacillus anthracis toxin

Tripartite AB-type (A2B) toxin

28

What are the three components of Bacillus anthracis toxin?

Binding (Protective Antigen)
Lethal Factor
Edema Factor

29

What does Bacillus anthracis Lethal Factor do?

It is a MAP Kinase Protease responsible for necrosis

30

What does Bacillus anthracis Edema factor do?

It is a calmodulin-dependent adenyl cyclase
It makes cAMP, which causes H2O secretion into tissues

31

Both virulence factors of Bacillus anthracis (______, ________) are encoded by ______.

(Toxin, Capsule)
Plasmid Encoded

32

How do you treat Bacillus anthracis?

Penicillin (cutaneous), Doxycycline, Ciprofloxacin

33

How is Bacillus anthracis controlled?

Live pXO2 vaccine
PA toxoid vaccine (military)
Livestock vaccine

34

Describe the physical structure of Brucella

G-
Aerobic Coccobacillus

35

T or F. Brucella is dangerous due to its rapid growth rate.

F. Very Slow growing (5 days on plate)

36

Growth site of Brucella in host?

Facultative Intracellular parasite

37

Four species of Brucella that affect humans?

Brucella melitensis (goats)
Brucella abortus (cattle)
Brucella suis (swine)
Brucella canis (dogs)

38

In what animal population is Brucella becoming more common?

Dogs -- spreading through animal shelters
Up to 10% prevalence in kennels

39

Clinical presentation of Brucella?

1-6 week incubation
Undulant Fever
May become chronic -- weakness
Granulomas (Liver, Spleen, LN, bone)
Psychoneuroses

40

What is an Undulant Fever?

Fever that goes up and down on a regular basis
(rise in afternoon, drop w/ profuse sweating in evening)

41

How may Brucella present in livestock (esp cattle)?

Bacteria bind erythritol in testes, placenta, or mammary tissue
If on placenta, form foci that detach microvilli
Abortion Storm

42

What is an abortion storm?

Large scale abortions throughout an animal population

43

How is Brucella in cattle so common out West?

Wild animals (Bison, goats, elk, sheep) carry it
Male transmits in semen
Abortion storm contaminates pasture grass

44

How do humans acquire Brucella?

Infected milk
Handling Infected Animal
Lab Accident

45

How is Brucella diagnosed?

Blood Sample
Serology
Culture

46

Pathogenesis of Brucella?

Intracellular survival in PMNs/Macrophages
Spreads to lymphatics and bloodstream
Infects liver, spleen, BM -- Forms granulomas
Bacterial growth -- Inflamm. response

47

So...what actually causes the undulant fever?

Bacterial release from macrophages
Brought back down as it is taken back in by macrophages

48

How can Brucella be controlled?

Pasteurize Milk
Eradicate from herds/Segregate from wild herds
Testing/Slaughter of Infected Animals

Human Live Vaccine in Russia

49

Why don't Americans vaccinate for Brucella?

We don't want to deal with the whole LPS toxicity thing.

U-S-A, U-S-A, U-S-A

50

How is Brucella treated?

Doxycycline + Rifampin +/- Streptomycin

51

Why might treatment tend to be ineffective?

Intracellular pathogen

52

If you see an elevated erythrocyte sedimentation rate and C-Reactive Protein, what should you suspect?

Inflammation is happening

53

Describe the structure of Francisella tularensis?

Small G- Coccobacillus
Pleomorphic
Slow Growth

54

Francisella tularensis have a fastidious requirement of...

Cysteine

55

Clinical Presentation of Francisella tularensis?

2-6 days Incubation
Inflamed, Ulcerated Papule at Infection Site
High Fever, Severe Toxemia
Abscess Formation in Liver, Spleen, LN, Lungs

56

Francisella tularensis is commonly found on what part of the body?

Hands (from skinning animals)

57

Reservoirs for Francisella tularensis?

Type A -- Rabbits (Most Severe)
Type B -- Beaver/Rodents (Milder)

58

Area of the country that looks like its got Francisella tularensis all over it?

Missouri, Arkansis, Oklahoma

59

Three methods of human acquisition of Francisella tularensis?

Skinning Infected Animals (and aerosol inhalation of carcass)
Ticks/Deerflies (maybe other biters)
Laboratory Hazards (Ingestion, Inhalation)

60

How infection is Francisella tularensis?

Infectious dose = 10 bacteria
Need P3 containment lab to grow it

61

Pathogenesis of Francisella tularensis?

Capsule resists complement
Take up by mphages by coiling phago.
Prevents oxidative burst, grows intracellularly
T4SS + effectors that prevent phagolyso fusion
LPS and PG release

62

How is Francisella tularensis treated?

Doxycycline, Cipro, gentamycin

63

Ways of controlling Francisella tularensis spread?

Strict isolation of lab organisms
Care while skinning rabbits
live cel vaccine for military

64

Francisella tularensis has a PAI with 17 genes. What is a PAI?

Pathogenic Island in the genome that contains genes that mediate pathogenicity

65

Describe the structure of Pasteurella multocida?

Small G- coccobacilli
Bipolar Staining

66

Oxygen requirements of Pasteurella multocida?

Facultative Anerobe

67

How many capsular antigen types of Pasteurella multocida are there?

4

68

Clinical presentation of Pasteurella multocida in humans?

Local or disseminated edematous soft tissue abscess
Occurs within a few hours of animal bite
Rapidly progressive cellulitis

You see proximal streaking along a lymph tract

69

Significance of Pasteurella multocida in the animal kingdom?

Fowl cholera (pneumonia) -- wipes out flocks
Shipping Fever (cattle) -- Copious nasal discharge,
septicemia, acute pneumonia, death
Snuffles (rabbits) -- progress to lethal hemorrhagic pneumonia

70

How does Pasteurella multocida typically spread to humans?

Animal bites (Carried by 90% cats and 70% of dogs)
Sometimes fomites (dust -- chicken shed workers)

71

Pathogenesis of Pasteurella multocida?

Antiphagocytic Capsule
Pili, Adhesion Proteins, Fe-binders
Adhere to mphage, but not engulfed
Growth and abscess formation

72

What is unique about the growth of Pasteurella multocida?

in vivo is as fast as in vitro
Grows too fast for immune system to keep up very well.

73

Is Pasteurella multocida very susceptible to antibiotics? Why?

No -- Grows too fast

74

How is Pasteurella multocida treated?

Multiple Drugs
Pen/Amp or Ceph + Tetra

75

Remember, most animal bites are....

Polymicrobial

76

Describe the physical structure of Bartonella henselae.

Gram negative small rod

77

Difference between Bartonella henselae and Rickettsia?

Bartonella henselae can grow on Lab Media

78

What does Bartonella henselae attach to in cats? humans?

Cats -- RBCs
Humans -- Endothelial Cells (Intracellular)

79

Describe the clinical presentation of Bartonella henselae.

Cat Scratch disease
Papule at inoculation site, local swelling, fever
Regional Lymph Node Involvement
Occasionally "Culture Negative" Endocarditis

80

Describe the clinical presentation of Bartonella quintana.

Trench Fever/Homeless Fever
5 day recurring fever
Headache, lymphadenopathy

81

What is Bacillary angiomatosis?

Proliferation of small spherical blood vessels in an inflamed endothelial background (blood vessel tumor)
May occur as papular/tumoral lesion or in organs

82

What bacterium cause Bacillary angiomatosis?

Bartonella henselae
Bartonella quintana
Bartonella bacilliformis

83

Who is more likely to get Bacillary angiomatosis?

Immunocompromised/AIDS patients

84

What causes Bartonella henselae.

Cat Scratches or Bites
#1 Cause of localized lymph node swelling in children

85

How is Bartonella quintana is spread by...

..human head and body lice.

86

Describe Bartonella pathogenesis.

Outer Membrane Binding Protein
T4SS + Effector Protein
Produces Cell-Stimulating Factor

87

What does Effector Protein do?

Ruffling of the membrane to promote endocytosis
Stops Phag-lys fusion

88

What does Cell-stimulating factor do?

Stimulating NF-kB and induces apoptotic pathways

89

How would you typically treat Cat Scratch disease?

You wouldn't

90

What can you use to treat Bartonella?

Azithromycin +/- Rifampin

91

Elevated Liver enzymes are typically indicators of what two things.

1) Liver Involvement
2) Muscle Breakdown/Rhabdomyolysis

92

What would you expect to see change in a CBC if you have cellulitis and nothing else.

No major CBC changes.

93

Two common polymicrobial infections.

Animal Bites
Abscess

94

Why do you take Ab levels early in an infection?

As a baseline

95

Describe the structure of Leptospira interrogans.

Exceedingly this spirochete
Seen on SEM
Endoflagella

96

Describe the difficulty in growing Leptospira interrogans.

Pretty easy for a spirochete -- 6 days to visible col.

97

How do Leptospira interrogans get energy.

Long-chain F.A.
No glycolysis

98

Clinical presentation of Leptospira interrogans initial stage.

Fever from bacteremia
Capillary Vasculitis and edema
leakage of RBCS and Serum (Petechiae, Bleeding)
Bac eliminated everywhere but liver, kidneys, CNS, eyes

99

Clinical presentation on Leptospira interrogans secondary

Weil's Disease
- Jaundice from liver failure
- Nitrogen retention in Kidney Medulla Destruction
Bloodshoot, Ooozing Eyes
Meningitis

100

How is Leptospira interrogans typically contracted?

Shed into water from infected kidneys
Persists in fresh water and is ingested
Also spread in rat and dog urine

101

Describe the pathogensis of Leptospira interrogans.

Intracellular growth possible
Pathogenesis from endothelial damage in capillaries
-- Highly perfused organs more affected (liver, kidneys)

102

How is Leptospira interrogans treated?

Antibiotics are of limited control
Macrolides or Quinolones can be used

103

How is Leptospira interrogans controlled?

Prophylactic Doxycycline by the military
Avoid rat-contaminated water
Vaccinate dogs

104

What does ANP indicate

Heart Damage (should be under 100)

105

Treatment for cellulitis.

Clindamycin, Keflex
Penicillin for likely MRSA coinfection