Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology 484 > Anaerobes > Flashcards

Anaerobes Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Purpose of aerotolerance test

A

Both BAP & CNA plate should be used to differentiate between true anaerobes & capnophiles. Used to determine whether microbes are strict anaerobes or only facultative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Procedure of aerotolerance test

A

The same organism is placed on two plates - one is incubated aerobically, the other anaerobically. If only the anaerobe plate org grows, then anaerobe. If the org grew on aerobic and anaerobe, then aerobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

BBE agar

A

Selective/differential for Bacteroides fragilis

Turns black due to the org’s ability to hydrolyze esculin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

EYA agar

A

Differential; used to detect lecithinase, lipase, & protease activity (Source from egg)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Nagler test

A

On EYA agar, C. perfringens antitoxin type A is smeared on 1/2 of the plate, then org is inoculated across both sides of plate. Pos test result is the lack of lecithinase activity on the half plate with antitioxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What test has replaced the Nagler test?

A

Reverse CAMP test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Bacteriostatic effects of O2 on anaerobes

A

If O2 is introduced, the org is busy trying to reduce the molecular oxygen & uses energy that is needed for metabolism, so can’t reproduce = static growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Bactericidal effects of O2 on anaerobes

A

Superoxide anions, hydroxyl radicals & hydrogen peroxide all build up, causing a cidal effect because anaerobes have few enzymes to effectively protect themselves from these byproducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why anaerobes need an environment that has a low redox potential? (media)

A

There are certain anaerobic growth enzymes that require fully reduced sulfhydryl groups to be present to sustain life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why anaerobes need an environment that has a low redox potential (in vivo)

A

These sulfhydryl groups are provided by other “NF” that are present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where anaerobes are located in the body

A

Skin, upper resp, female genital tract, GI tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where anaerobes are located in the environment

A

Soil, fresh & salt water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
  1. Bacteroides fragilis
  2. Porphyromonas/Prevotella
  3. Fusobacterium nucleatum
  4. Clostridium species
  5. Actinomyces israelii
A

5 most commonly found anaerobes in infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

SPS disk

A

sodium polyanethol sulfonate

gm +c Peptostreptococcus anaerobius is susceptible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Nitrate disk

A

Nitrate -> nitrite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Bile disk

A

to test if org can grow in 20% conc. of bile

gram neg rod that’s 20% bile resistant is Bacteroides fragilis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Catalase

A

Clostridium: catalase =
Bacillus: catalase +

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Gas liquid chromatography

A

Match peaks & time of peaks with known organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Biochemical based mini-systems

A

IDs in 24-48 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Enzyme based mini-systems

A

ID in 4 hours

Ex. Vitek, Rapid Ana II, Microscan

21
Q

C. botulinum food poisoning

A

Toxin produced by org is ingested in contaminated food & absorbed in small intestine. Toxin attaches to neuromuscular junction of affected nerves, causing paralysis along with other symptoms.

22
Q

C. perfringens food poisoning

A

Mild, self-limited GI tract. Illness approximately 8-12 hours after ingestion of contaminated food. Type C is more severe

23
Q

What anaerobe is responsible for pseudomembranous colitis?

A

C. difficile - caused by antimicrobial therapy or from hospital workers not washing hands

24
Q 
EYA lecithinase +
Nagler test: C +
Reverse CAMP +
Brucella/Blood Agar: double zone beta hemolysis
Gelatin hydrolysis & DNase pos
A

Presumptive ID for C. perfringens

25
Q

Definitive ID for C. perfringens

A

Enzyme based mini-system

26
Q

Actinomyces
Eubacterium
Lactobacillus

A

Non-spore forming anaerobic gram pos bacilli

27
Q

Bifidobacterium
Mobiluncus
Propionibacterium

A

Non-spore forming anaerobic gram pos bacilli

28
Q

Propionibacterium pathogenicity

A

NF of skin & can cause subacute bacterial endocarditis & bacteremia

29
Q 
Catalase +
Spot indole +
Anaerobic gram pos diptheroid
Pleomorphic gram pos rod
Gelatin hydrolysis pos
A

Presumptive ID of Propionibacterium

30
Q

Actinomyces israllei

A

Seldom obligate anaerobes, colonies are rough, spider-like or wooly

31
Q

Actinomyces israllei ID

A

Catalase, spot indole, & gelatin neg

32
Q

Actinomycosis

A

chronic granulomatous infection with lesions that erupt from infected sinus & drain pus containing sulfur granules

33
Q

Anaerobic gram neg bacilli

A

Bacteroides
Prevotella
Prophyromonas
Fusobacterium

34
Q 
Catalase +/=
Indole =
DNase =
Penicillin R
Rifampin S 
Kanamycin R
Pigment = 
Bile Solubility R
A

Bacteroides fragilis

35
Q 
Catalase =
Indole +
DNase =
Penicillin S/R
Rifampin S 
Kanamycin S
Pigment = 
Bile Solubility S
A

Fusobacterium

36
Q 
Catalase =
Indole +
DNase =
Penicillin S/R
Rifampin S 
Kanamycin R
Vancomycin S
Pigment +
Bile Solubility S
A

Porphyromonas

37
Q 
Catalase =
Indole +
DNase +
Penicillin S/R
Rifampin S 
Kanamycin R
Vancomycin R
Pigment +
Bile Solubility S
A

Prevotella

38
Q

Gram Pos Anaerococcus sp

A

Finegoldia spp
Peporiphilus spp
Peptococcus niger
Peptostreptococcus spp

39
Q

Gram neg anaerococcus

A

Veillonella

40
Q

Presumptive peptostreptococci ID

A

anaerobic gram pos cocci

41
Q

Peptostreptococcus anaerobius ID

A

SPS sensitive

42
Q

Peptostreptococcus asaccharolyticus

A

SPS resistant

43
Q

What is the genus of the anaerobic gram neg cocci?

A

Veillonella

44
Q

Veillonella chemical ID

A

Gram neg cocci

Nitrate pos

45
Q

CLSI suggestions for susceptibility testing

A

Not required for most anaerobic cultures except:

  1. Known resistant organism
  2. Failure of treatment
  3. Very serius outcome
  4. No literature available on empiric
  5. Particular sites that warrant susceptibility testing
  6. Particular organisms that warrant susceptibility testing
46
Q
  1. Penicilllin G
  2. Broad spectrum penicillins (carboxy penicillins such as ticarcillin
  3. Combination agent (B lactam antibiotic & B-lactamase inhibitor)
  4. Other B-lactam antibiotics (cefoxitin & impenem)
  5. Other: chloramphenicol, clindamycin, metronidazole, tetracycline, trovafloxicin
A

Common antimicrobial agents used

47
Q

Problems encountered with Anaerobe susceptibility testing

A
  1. Not all of them will grow on same media so reproducibility is poor
  2. Relatively high costs
  3. Lack of comparability between methods
48
Q

Epsilometer test (E test)

A

Inhibition ellipse allows for an MIC & also several drugs (strips) can be used on one plate

Microbiology 484 (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions