Antimicrobial chemotherapy Flashcards

1
Q

What are bacteriostatic agents?

A

Inhibitors of protein synthesis - they bind to ribosomes

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

If the concentration of the bacteriostatic agent is lowered, growth of microbe resumes. True or false?

A

True

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

When a bacteriostatic agent is given, both the total cell count and the viable cell count stay the same. True or false?

A

True

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

What are bacteriocidal agents?

A

Bind tightly to cells and kill them

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

Are dead cells destroyed when administering a bacteriocidal agent?

A

No

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

What happens to the total cell count and viable cell count when a bacteriocidal agent is used?

A

Total cell count remains the same

Viable cell count decreases

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

What is a bacteriolytic agent?

A

Kills cells by lysis

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

What happens to the total cell count and the viable cell count when bacteriolytic agent is given?

A

Both decrease

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

What are the two ways in which antimicrobial activity can be measured?

A

Minimum inhibitory concentration (MIC)

Disc diffusion assay

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

What does the MIC indicate?

A

The minimum amount of agent needed to inhibit growth of a test bacterium

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

What does disc diffusion assay do?

A

Determines the zone of inhibition

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

Can antiseptics be used on living tissue?

A

Yes - non toxic

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

Biocides sterilise. True or false?

A

False - not necessarily

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

What does the efficacy of a biocide depend on?

A

microbial load
concentration of biocide used
presence of organic matter

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

What is the most resistant microbe to biocides?

A

Prions

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

What is the least resistant microbe to biocides?

A

Gram positive bacteria

17
Q

Are mycobacterium more or less resistant to biocides than gram negative bacteria?

A

More resistant

18
Q

Are spores more or less resistant to biocides than prions?

A

Less

19
Q

What is meant by intrinsic resistance?

A

The bacterium lacks the structure that the antibiotic targets. E.g. mycoplasmas don;t have a cell wall so they are resistant to penicillin (targets cell wall) OR
bacterium is impermeable therefore has low level of uptake of antibiotic - e.g. produces biofilm

20
Q

What is meant by extrinsic resistance?

A

Bacteria produces degradative enzymes e.g. Staph produce B-lactamases which cleave penicillin
Bacteria modify target site
Pump agent out of cell: efflux

21
Q

What drives antimicrobial resistance?

A

Not finishing the course
Use of inappropriate antimicrobials
Poor infection control

22
Q

Bacteriophages are new antimicrobials that can be used. What are they?

A

Viruses that infect the bacteria