L30 - Gram+ Bacteria III Flashcards Preview

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Flashcards in L30 - Gram+ Bacteria III Deck (28):
1

Clostridia

microbiology

 

  • Gram+
  • bacillus (racquet-shaped)
  • obligate anaerobes
  • capable of forming spores

2

Clostridia tetani

pathogenesis

  • Spores introduced from soil through a wound
  • Bacteria grow and lyse in injured, anoxic wounds, and they release toxins
  • Toxins transported intra-axonally to spinal neurons

3

Clostridia tetani

toxins

  • tetanospasmin
    • Heavy chain - binds irreversibly to eukaryotic cells
    • Light chain - blocks inhibitory receptors of muscle contraction
  • tetanolysin

4

Clostridia tetani

clinical manifestations

  • Lock jaw
  • Muscle spasming

5

  • Gram+
  • bacillus (racquet-shaped)
  • obligate anaerobes
  • capable of forming spores

Clostridia

microbiology

 

6

  • Spores introduced from soil through a wound
  • Bacteria grow and lyse in injured, anoxic wounds, and they release toxins
  • Toxins transported intra-axonally to spinal neurons

Clostridia tetani

pathogenesis

7

  • tetanospasmin
    • Heavy chain - binds irreversibly to eukaryotic cells
    • Light chain - blocks inhibitory receptors of muscle contraction
  • tetanolysin

Clostridia tetani

toxins

8

  • Lock jaw
  • Muscle spasming

Clostridia tetani

clinical manifestations

9

Clostridum botulinum

pathogenesis

  • Heat resistant
    • Boiling actually helps by creating an anaerobic environment
    • Destroy toxin through pressure cooker
  • Ingestion through food
  • Release of neurotoxin in bloodstream

10

Clostridia botulinum

toxicity

  • Spores are only toxic in babies, adults are only prone to the toxin itself
    • Honey should be avoided
  • Neurotoxin prevents release of Ach
    • Light chain prevents release of Ach
    • Heavy chain binds the receptor
  • Muscles are unable to contract

11

Clostridia botulinum

clinical manifestations

  • Cranial nerve impairment
  • Paralysis

12

  • Heat resistant
    • Boiling actually helps by creating an anaerobic environment
    • Destroy toxin through pressure cooker
  • Ingestion through food
  • Release of neurotoxin in bloodstream

Clostridum botulinum

pathogenesis

13

  • Spores are only toxic in babies, adults are only prone to the toxin itself
    • Honey should be avoided
  • Neurotoxin prevents release of Ach
    • Light chain prevents release of Ach
    • Heavy chain binds the receptor
  • Muscles are unable to contract

Clostridia botulinum

toxicity

14

  • Cranial nerve impairment
  • Paralysis

Clostridia botulinum

clinical manifestations

15

Clostridia perfringens

cause of gas gangrene

16

cause of gas gangrene

Clostridia perfringens

17

Clostridia difficile

  • Common hospital acquired diarrhea
  • Toxins
    • Toxin A
      • Largest bacterial toxin
      • Binds to carbohydrate receptors, causing cell destruction and fluid accumulation
    • Toxin B

18

  • Common hospital acquired diarrhea
  • Toxins
    • Toxin A
      • Largest bacterial toxin
      • Binds to carbohydrate receptors, causing cell destruction and fluid accumulation
    • Toxin B

Clostridia difficile

19

Bacillus anthrax

pathogenesis

  • Herbivores digest spores from soil
  • Humans acquire bacteria from animals or infected surfaces
  • bacteria lives within macrophages after being phagocytosed

20

Bacillus anthrax

toxins

  • Protective Antigen: forms membrane channel
  • Edema Factor: adenylate cyclase; EF and PA form edema toxin together
  • Lethal Factor: LF and PA form lethal toxin
    • Causes necrosis

21

Bacillus anthrax

clinical manifestations

  • Itching papule that becomes an eschar
  • Widened mediastinum (space between lungs on X-ray)

22

  • Herbivores digest spores from soil
  • Humans acquire bacteria from animals or infected surfaces
  • bacteria lives within macrophages after being phagocytosed

Bacillus anthrax

pathogenesis

23

  • Protective Antigen: forms membrane channel
  • Edema Factor: adenylate cyclase; EF and PA form edema toxin together
  • Lethal Factor: LF and PA form lethal toxin
    • Causes necrosis

Bacillus anthrax

toxins

24

  • Itching papule that becomes an eschar
  • Widened mediastinum (space between lungs on X-ray)

Bacillus anthrax

clinical manifestations

25

Bacillus cereus

toxins

  • Emetic: vomiting
  • Diarrheal: diarrhea

26

Bacillus cereus

pathogenesis

  • Spores germinate while rice is cooked
  • Bacteria grow as rice cools

27

  • Emetic: vomiting
  • Diarrheal: diarrhea

Bacillus cereus

toxins

28

  • Spores germinate while rice is cooked
  • Bacteria grow as rice cools

Bacillus cereus

pathogenesis