Anaerobes (from chart) Flashcards Preview

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Flashcards in Anaerobes (from chart) Deck (56):
1

General features of anaerobes

-Mixed infections

-remove toxic O2 forms

-fermentation

 

2

Anaerobes live at _____

low redox potential (generated by other organisms)

3

Anaerobes produce ______

abcesses

4

Anaerobes (general) virulence factors?

-Normal flora that enter unprotected areas

-anaerobiosis either exits or generated by other organisms

-tissue destructive enzymes -> abcesses

5

Common anaerobic abcesses...

  1. Abdominal
  2. Salpingitis
  3. Lung
  4. URT
  5. Brain

6

All anaerobic organisms

  1. Bacterioides fragillis
  2. Prevotella melaninogenica
  3. Porphyromonas gingivalis
  4. Fusobacterium
  5. Peptostreptococcus
  6. Propionibacterium
  7. Clostridium (bot, tet, perf, diff)

7

Anaerobic Gram Negative bacteria

Bacterioides, Prevotella, Porphyromonas, Fusobacterium

8

Anaerobic Gram Positive bacteria

Peptostreptococcus, Propionibacterium, Clostriduim

9

Anaerobe bacteria treatment

Drainage*

PenG

Metronidazole and Clindamycin

 

*Drainage allows O2 in

10

PenG not given to _____ and _____

Because they are ______________

Bacterioides and Prevotella

Beta-Lactam resistant

11

2nd line Antibiotics for Anaerobes

 

2nd and 3rd gen Cephalosporins and Carbapenems

12

Bacterioides Structure

Gram - Rod

13

Bacterioides features

 

60% of abdominal bacteria

Can live as monoculture

14

Bacterioides clinical

-Colonic

-70% of anaerobic bacteremia

Most common

15

Bacterioides virulence

 

  1. Antiphagocytic capsule
  2. Enzyme production
  3. LPS

16

Bacterioides enzymes

-SOD and Catalase

-Neuraminidase and Heparinase

17

Prevotella Structure

Gram - Coccobacillus

18

Prevotella clinical

-Oral

-Brain and Lung abcesses

19

Prevotella enzymes

 

Collagenase

20

Porphyromonas structure

Gram - Rod

21

Porphyromonas Clinical

-Oral

-Gingivitis

-Oral Abscess

22

Carriers of Porphyromonas

Warm and moist areas

-Axilla, groin, perineum

23

Fusobacterium structure

Gram - fusiform

24

Fusibacterium locations

Oral and Colonic

25

Fusibacterium Clinical

Infectious monoculture in osteomyelitis

26

Peptostreptococcus structure

Gram + coccus

27

Peptostreptococcus locations

Bacteremia

Pleura/lungs

28

Propionibacterium acnes structure

Gram + pleiomorphic rod

29

Propionibacterium location

 

-Skin (acne)

-Brain (abcess)

30

Clostridium Structure

Gram + rounded ends

in pairs or short chains

31

Clostridium bacteria are  _______ and _________

Spore-formers

Strict anaerobes

32

C. Botulinum clinical features

Flaccid paralysis (descending)*

-Dysphagia, Diplopia, Ptosis

 

*Starts with Cranial Nerves

33

C. Botulinum Carriers

-Home-canned foods

-Honey (floppy baby syndrome)

-Wounds

34

C. Botulinum Serotypes

A, B, E

35

C. Botulinum virulence

AB Neurotoxin

-B binds to Motor Neuron End plate

-A prevents ACH vesicle fusion

36

C. tetani incubation time

4d - 4 w

37

C. tetani clinical

Rigid paralysis

-trismus, ophisthotonos

-death- from spasm interefering with respiration

38

C. tetani carriers

Spores from penetrating fomites

Umbilical stump in neonatal tetanus

39

C. tetani virulence

AB neurotoxin*

  • B binds to NMJ
  • A retrograde transported to presynaptic inhibitory neuron
  • Inhibit GABA release

 

*plasmid encoded tetanospasmin

40

C. perfringens features

5 histotoxic strains

Others cause myonecrosis

 

41

C. Sordelli causes...

Postpartum infection

42

C. perfringens incubation

1-3 days infected wound suppurating

43

C. perfringens clinical

Foul discharge, necrosis, toxemia, shock, death

44

C. perfringens can also cause _____

Enteritis Necroticans (food poisioning)

 

**if ingested orally

45

C. perfringens carriers

spores (in food poisioning)

Injury to tissues

Ischemia (anoxic environment)

 

*Polymicrobial if others use O2 to reduce oxygen presence

46

C. perfringens virulence factors

a-toxin  (phospholipase)

b-toxin (enteritis necroticans)

Hyaluronidase

Enterotoxin

47

C. perfringens virulence effects

Leukocytosis

 

gas fermentation--> tissue distension--> vascular compression--> ischemia--> necrosis--> toxemia

48

C. diff incubation

4-10 days secondary to Rx treatment

 

49

Drugs that carry C. diff risk

Broad spec clindamycin

prolonged use of PPI

50

C. diff clinical

May affect entirety or part of colon (= early watery diarrhea)

Pseudomembrane -- leukocytes penetrate gut epithelium and form white-yellow exudate

 

51

C. diff carriers/origin

Normal flora (impt for Treg development)

Antibiotics (disrupt flora)

DIsseminated in diarrhea

Nosocomial -- 94%

52

C. botulinum Tx

Trivalent (ABE) or Polyvalent Antitoxin immediately

NO AB because not infection

53

C tetani vaccine

Tdap + boosters

54

C. tetani Tx

-TIg antitoxin (early!)

--Tracheostomy

-Muscle relaxant  (MgSO4)

-Metronidazole

55

C. perfringens Tx

Amputation & Debridement

PenicillinMetronizadoleClindamycin

56

C. diff Tx

  1. Stop Antibiotic, replinish flora
  2. fluids
  3. Anti-Toxin B Antibodies
  4. Vancomycin, Metronidazole
  5. Fidaxomicin
  6. Fecal replacement therapy