Brainscape's Knowledge GenomeTM

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


See full index

Medical Microbiology > L6: Anti-Infective Therapy > Flashcards

L6: Anti-Infective Therapy Flashcards

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

____: drug used to treat any disease

____: substance that interferes with proliferation of microorganism

____: drug of natural origin (often dirt) that has anti-microbial properties

A

Chemotherapeutic
Antimicrobial
Antibiotic

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

True or False: Bacteriocidal antimicrobials inhibit growth while bacteriostatic kills

A

False
Bacteriocidal = kills
Bacteriostatic = inhibits growth

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

Which of the following antimicrobials would you give to an immune compromised patient or one with a lethal condition?
A. Bacteriostatic
B. Bacteriocidal

A

B. Bacteriocidal

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

True or False: A functioning immune system is required for use of bacteriocidal

A

False - required for bacteriostatic

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

What’s the difference between drug resistance and sensitivity?

A

Resistance: NOT inhibited by clinically achievable drug concentration

Sensitivity: Inhibited by clinically achievable drug concentration

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

True or False: Anti-microbials tests are all ex-vivo

A

False - all in vitro

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

Which tests are used to determine whether abx tx is effective at treating patient infection?

A

Antimicrobial sensitivity testing

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

What are the four antimicrobial sensitivity tests?

A

1) Kirby Bauer - QUALITATIVE
2) Minimum Inhibitory Concentration (MIC)
3) Minimum Bacteriocidal Concentrations (MBC)
4) Antimicrobial Serumcidal Concentrations

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

To read a Kirby-Bauer plate, measure the _____

A

zone of inhibition

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

What are the results of a Kirby-Bauer test?

A

1) Susceptible
2) Intermediate
3) Resistant

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

Which test is used to determine the LEAST amount of an antimicrobial agent required to inhibit growth (static or cidal)

A

Minimum Inhibitory Concentration.

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

Which test is used to determine the LEAST amount of an antimicrobial agent required to inhibit growth (static or cidal)
A. Kirby Bauer
B. Minimum Inhibitory Concentration (MIC)
C. Minimum Bacteriocidal Concentrations (MBC)
D. Antimicrobial Serumcidal Concentrations

A

B. Minimum Inhibitory Concentration (MIC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

True or False: Treatment should not exceed the MIC at site of infection

A

False - treatment SHOULD exceed the MIC at site of infection

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

How is the growth assesed in the MIC?
A. Plating cell suspensions
B. Turbidity
C. Size

A

B. Turbidity

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

In which of the following tests is an antibiotic diluted in broth containing the pt’s isolated in standard amounts and incubated?
A. Kirby Bauer
B. MIC
C. MBC

A

B. MIC

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

True or False: MBC test can be adapted to E test or microwell plate

A

False - MIC can

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

Which of the following tests is used to identify the MINIMUM amount of an antimicrobial agent required to KILL (bacteriocidal)?
A. Kirby Bauer
B. MIC
C. MBC

A

C. MBC

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

True or False: Both Kirby Bauer and MIC can inhibit growth that is either static or cidal

A

True

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

True or False: The MIC is always greater than or equal to the MBC. In some cases, levels that are less than or equal to the MBC are needed for efficacy

A

False
- MIC is always < or equal to MBC
- In some cases, levels greater than or equal to MBC are needed for efficacy

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

In the case where infection is inaccessible to immune system, the amount of anti-micobial at the site should ____ MBC

A

exceed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

___ is determined by plating cell suspensions from MIC test (an extension of MIC assay)

A

MBC

22
Q

Which test is used to identify the minimum concentration of an antimicrobial agent required to kill a patient’s isolate in the patient’s serum?

A

Antimicrobial Serumcidal Concentration

23
Q

True or False: Following an Antimicrobial Serumcidal Concentration treatment, patient’s serum is serially diluted with standard amount of their isolate, followed by incubation, to determine if MBC has been achieved

A

True

24
Q

Which of the following is NOT a benefit of antibiograms?
A. Cost effective
B. Reserve certain antimicrobials for specific situations
C. Reduce antibiotic-resistance
D. Increase antibiotic-resistance
E. Aid in selection of appropriate antibiotic tx

A

D. Increase antibiotic-resistance

25
Q

True or False: Good selective toxicity means that the antimicrobial chemotherapeutic agent has an EXCLUSIVE target in the microbe

A

True

26
Q

Do cell membrane active agents have poor or good selective toxicity?

A

Poor

27
Q

Do cell wall active agents (exclusive target in microbe) have poor or good selective toxicity?

A

Good

28
Q

What features of an abscess lead it to be poorly penetrated by antimicrobials?

A

Low O2 levels
Low perfusion
Tissue necrosis

29
Q

True or False: There are excess metabolic targets for antimicrobials in abscess

A

False - there are fewer

30
Q

In abscesses, most phagocytes in lesions are dead, meaning new __ and __ can’t reach the site

A

WBC; antibodies

31
Q

The presence of which two host metabolites (in abscess) often interfere w/antimicrobials?

A

Excess folic acid and sulfonamides

32
Q

When treating an abscess, ____ lose effectiveness at lower pH

A

Aminoglycosides

33
Q

What is a major limitation of antimicrobials, specifically for those who are immunocompromised?

A

immunosuppression

34
Q

True or False: Superinfections (treat one disease and a new and different disease appears at another site) are commonly seen with use of antibacterials

A

False - common with antimicrobials

35
Q

____: Administration of drugs to patient who is not infected, but is still at increased risk of acquiring infections

A

Chemoprophylaxis

36
Q

True or False: Prevention of 2 bacterial pneumonia s/p flu or clean surgery that does not breech the mucosa are examples of justified chemoprophylaxis

A

False - unjustified!

37
Q

_____: The administration of 2 or more antibiotics in combination

A

Combinatorial Therapies

38
Q

A patient has polymicrobic, life-threatening infection and severe neutropenia. They are also
immunocompromised. Are the a good candidate for combination chemotherapy?

A

Yes
1) Life threatening infection
2) polymicrobial infection
3) severe neutropenia
4) immunocompromised

39
Q

True or False: Combination chemotherapy is justified if doing so allows you to lower the dose of a toxic drug while also increasing cidal activity

A

True

40
Q

____: two or more drugs which, when used in combination, are CIDAL at concentrations lower than that of either component used separately
A. Additive Effect
B. Antagonism
C. Indifference
D. Synergism

A

D. Synergism

41
Q

Which two drugs display synergism?

A

Penicillin
Aminoglycosides

42
Q

___: can be used to reduce toxicity, but to a lesser extent than synergistic drugs

A

Additive Effect

43
Q

___: can be used to reduce toxicity, but to a lesser extent than synergistic drugs
A. Additive Effect
B. Antagonism
C. Indifference
D. Synergism

A

A. Additive Effect

44
Q

____: reduction in activity of one or both components of the therapy when both are present
A. Additive Effect
B. Antagonism
C. Indifference
D. Synergism

A

B. Antagonism

45
Q

Which two drugs, when used together, exhibit antagonism?

A

Tetracycline and Penicillin

46
Q

___: combined action of either drug is the same as with either component alone
A. Synergism
B. Additive Effect
C. Indifference

A

C. Indifference

47
Q

What are four mechanisms of drug resistance?

A

1) Alteration of drug target - modification of target site
2) Prevent access of drug to target
3) Inaction of drug
4) Tolerance

48
Q

True or False: Efflux pumps are used to prevent access of drug to target

A

True

49
Q

True or False: Altered PBP’s can reduce sensitivity to B-lactams while altered DNA Gyrase reduces sensitivity to fluroqunolones. These are just a few examples of alteration of drug target (modification of target site)

A

True

50
Q

What is an example of an enzyme made by a microbe to inactivate a drug?

A

Penicillinase

51
Q

No change in MIC but MBC increases by a factor of 32. This is an example of ___

A

tolerance

52
Q

One mechanism of resistance is tolerance. In tolerance, evasion of killing can occur via: slowing growth rate (___) or depressing production of key enzymes involved in cell wall synthesis (____)

A

phenotypic
genotypic

Medical Microbiology (31 decks)

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