Lecture 12 Flashcards by Carter Duggan

Bacillus has what shape and stain?

GramPos (first that we have looked at)
Rods, large, fat, square ends
In chains, palisades, clumps

How well did you know this?

Not at all

Perfectly

What is the oxygen environment for bacillus?

Aerobic (some species have pathways for butanediol of lactate fermenation)

How well did you know this?

Not at all

Perfectly

Where is bacillus found?

Soil and leaf surfaces

How well did you know this?

Not at all

Perfectly

Bacillus cereus is what kind of disease?

Food poisoning (not zooniosis like other bacillus)

How well did you know this?

Not at all

Perfectly

Why is bacillus not found in a hosts blood stream?

They are spores

How well did you know this?

Not at all

Perfectly

What are the two types of bacillus cereus?

Emetic variety-(like staph)
Diarrheal variety (like c-diff)

How well did you know this?

Not at all

Perfectly

B. cereus emetic v. presents how?

Acute N/V and cramps (1 hour)

Resolves in 1 hour

How well did you know this?

Not at all

Perfectly

B. cerues diarrheal c. presents how?

Slower onset diarrhea and cramps (6-8 hours)

No vomiting

How well did you know this?

Not at all

Perfectly

What foods are implicated in B. cereus infections?

Cooked pasta and rice (spores germinate and produce toxins)

How well did you know this?

Not at all

Perfectly

What are the four toxins of B. cereus?

Emetic toxin (K+ ionophore)
3 enterotoxins:
Hemolytic
Non-hemolytic (forms pores)
Cytotoxin (activates ad. cyc.)

How well did you know this?

Not at all

Perfectly

What is the form of B. anthracis that is encounted?

Central spores

looks like cut glass colonies on blood agar and no hemolysis

How well did you know this?

Not at all

Perfectly

What type of capsule does B. anthracis have?

Poly-D glutamate

How well did you know this?

Not at all

Perfectly

What is clinical presentation of B. anthracis

Papule becomes a large necrotic eschar in 12-36 hours

Disseminates and may affect organs

How well did you know this?

Not at all

Perfectly

How can you get anthrax?

Touching
Eating
Breathing
(usually from handling infected animal products)

How well did you know this?

Not at all

Perfectly

How does anthrax cause illness?

Spores enter macrophages and germinate in phagolysosome upon exposure to ROS
Release a triparte AB toxin
B part binds to receptors and facilitates entry
A-lethal factor MAP kinase protease leads to necrosis
A-edema factor activates calmodulin dependent adenyl cyclase leads to water secretion

How well did you know this?

Not at all

Perfectly

What encodes the virulence factors of anthrax

Plasmid encoded (both plasmids are needed for full virulence)

How well did you know this?

Not at all

Perfectly

How do you treat cutaneous bacillus?

PCN

How well did you know this?

Not at all

Perfectly

How do you treat systemic bacillus?

Doxy

Cipro

How well did you know this?

Not at all

Perfectly

What is the vaccine for bacillus?

Live cell vaccine
PA toxoid vaccine (military)
New trial for immunoglobulin

How well did you know this?

Not at all

Perfectly

What is shape and stain of brucella?

GramNeg
Coccobacillus
Nonmotile

How well did you know this?

Not at all

Perfectly

What is oxygen profile for brucella?

Aerobic

How well did you know this?

Not at all

Perfectly

Where is brucella found in it’s host?

Obligate intracellular parasites (PMNs and macrophages)

How well did you know this?

Not at all

Perfectly

What are the four types of brucella humans can get?

B. melitensis (goats)
B. abortus (cattle)
B. suis (swine)
B. canis (dogs)

How well did you know this?

Not at all

Perfectly

What is incubation period for brucella?

1-6 months

How well did you know this?

Not at all

Perfectly

What is characteristic of brucella infection?

Undulant fever Granulomas in tissues (liver, spleen, lymph nodes) General weakness and malaise

What is a concern for how brucella can be spread by cattle?

Abortions caused by the organism can get on the grass. This can lead to infected milk. Can also get from: Handling infected animals Infected labs

What tissues are commonly affected by brucella?

Endothelium granulomas of liver, spleen, bone marrow

How does brucella cause disease on a molecular level?

No exotoxin so infection from bacterial growth

How do you treat for brucella?

Doxy Rifampin Streptomycin

Shape and stain of francisella tularensis?

``` GramNeg Small coccobacillus (pleomorphic) ```

Describe growth of francisella tularensis?

Slow growth | Needs cysteine

Francisella tularensis clincal presentation

Inflamed, ulcerated papule at site of infection High fever, severe toxemia Abscess in liver, spleen, lymph node, lungs

How is francisella tularensis transmitted

Skinning infected rabbits Ticks of deerflies Lab hazards

What is the pathogenesis of francisella tularensis?

Complement resistant capsule Taken up by macrophages via coiling phagocytosis Has LPS and PG PAI with 17 genes and T4SS mechanism

How do you treat francisella tularensis?

Doxy Cipro Gentamycin

Pasteurella multocida shape and stain

GramNeg Coccobacilli Bipolar staining which is hard to see

What is oxygen requirement for pasteurella multocida

Faculatative anaerobe

How many capsule types of pasteurella multocida have?

4 | A is the most common

How does pasteurella multocida present?

Local or disseminated soft tissue abscess | Can progress to cellulitis

How do we worry about pasteurella multocida in animals?

First it's a zoonosis | It can also kill many kinds of animals

How is pasteurella multocida often transmitted?

Almost always via animal bites | Occasionally via dust (fomites)

Pasteurella multocida pathogenesis?

Antiphagocytic capsule Adhere with special pili and Fe-binding proteins Adhere to macrophages but not engulfed Pathogenesis by growth and abscess formation

Why are in vivo use of antibiotics against pasteurella multocida not very effective?

It grows very fast

How do you treat pasteurella multocida?

Pen/Amp or Ceph + tetracycline

Bartonella henselae shape and stain

GramNeg Rods Looks like rickettsia

Why do cats give people Bartonella henselae

Protein that can attach to feline RBCs

Where is Bartonella henselae found in humans?

Intracellular

How does Bartonella henselae present in clinic

``` Papule at inoculation site Local swelling Fever Regional lymph node swelling Occassionally "culture negative" endocarditis ```

What disease does Bartonella henselae cause

Cat scratch fever

What diease does bartonella quintana cause?

Trench fever | 5 day fever, recurring

What is a third diease caused by bartonella (beside cat scratch and trench fever)?

Bacillary angiomatosis Proliferation of small spherical blood vessels in inflamed endothelial background Papular or tumoral lesion Man occur in organs too

How is bartonella quintana spread?

Human lice | Common among homeless

What is bacillary angiomatosis associated with?

AIDs

What is pathogenesis of bartonella?

Outer membrane binding protein Penetrate endothelial cells (T4SS) Produce CSF and NF-kB and induces apoptosis

How do you treat bartonella?

Usually don't for cat scratch fever | Azithromycin and rifampin for bacillary angiomatosis

Leptospira interrogans shape

Very thin spirochete

How do Leptospira interrogans move?

Endoflagella

What is metabolism of Leptospira interrogans

All from long chain fatty acids (no glycolysis)

How does Leptospira interrogans present?

Capillary vasculitis and edema in many organs (leakage of RBCs and serum)

Leptospira interrogans is eliminated from most places in the body with a few exceptions. What are they?

Liver, kidneys, CNS, eyes

What is the second stage of Leptospira interrogans

Weil's disease Jaundice due to liver failure Nitrogen retention from kidney medulla destruction Blood shot, oozing eyes Meningitis Nausea, vomiting, and intense pain from toxic organ failure

How is Leptospira interrogans transferred?

Organism can be shed into water via urine from infected kidneys Also from infected animal urine

Leptospira interrogans pathogenesis?

No toxins detected Intracellular growth possible Pathogenesis from endothelial damage in capillaries More severe in more perfused organs

Leptospira interrogans control?

``` Antibiotics not always useful Corticosteroids for kidney damage Macrolides and quinolones can be used Doxy used prophylactically by military when in contaminated water Vaccinate dogs against it ```