Brainscape's Knowledge GenomeTM

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


See full index

Systemic Pharm I > Antimicrobial Principles > Flashcards

Antimicrobial Principles Flashcards

1
Q

What factors (6) influence the antimicrobial agent chosen?

A

identity of organism, susceptibility, site of infection, patient factors, safety, cost

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

How do you identify the organism?

A

culture, gram stain, detection of antigens or nucleic acids, or host inflammatory response– culture must be preformed prior to treatment

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

As optometrists, drug choice is determined by:

A

site of infection and patient’s medical history… broad spectrum antibiotic is usually chosen

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

What is bacteriostatic?

A

arrest the growth and replication of bacteria and let body’s immune system eliminate the infection

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

What is bactericidal?

A

drugs kill bacteria, more aggressive and often used for seriously ill patients

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

What is MIC?

A

minimum inhibitory concentration- lowest concentration of an antibiotic that inhibits bacterial growth, must reach this level clinically to have an effect

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

What is MBC?

A

minimum bactericidal concentration- lowest concentration of antibiotic that kills the bacteria

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

What three things are entry to the CNS influenced by?

A

lipid solubility, molecular weight, and protein binding

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

What are some patient factors that can affect the immune system?

A

alcoholism, diabetes, HIV, malnutrition, autoimmune disease, pregnancy, age, immunosuppressive drugs

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

What are the 5 major patient factors for drug selection?

A

renal function, hepatic function, poor perfusion, age, and pregnancy

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

What happens if kidney function is poor?

A

accumulation of antibiotics

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

What is an example of an antibiotic among the least toxic of all drugs?

A

penicillin

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

What is an example of an antibiotic with serious potential for toxicity?

A

chloramphenicol

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

What administration is preferred for mild infections and outpatient treatment?

A

oral

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

Sometimes antibiotics are so poorly absorbed from GI….

A

they must have parenteral administration

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

What is rational dosing based on?

A

pharmacodynamics (relationship of concentration to effect) and pharmacokinetics (ADME)

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

What three properties have significant influence on rational dosing?

A

concentration-dependent killing, time-dependent killing, post antibiotic effect

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

What is concentration-dependent killing?

A

certain agents show significant increase in the rate of bacterial killing as the concentration of antibiotic increases (favor once a day bolus infusion) ex: aminoglycosides

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

What is time-dependent killing?

A

effect is best predicted by the percentage of time that blood concentrations remain above MIC– favor extended or continuous infusions exL b-lactam, macrolides

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

What is PAE?

A

post antibiotic effect– persistent suppression of microbial growth that occurs after antibiotic levels have fallen bellow the MIC

21
Q

How does a long PAE affect dosing?

A

only requires one dose a day ex: aminoglycosides and fluoroquinolones

22
Q

What are the six major families of antibiotics?

A

penicillins, cephalosporins, tetracyclines, aminoglycosides, macrolides, and fluoroquinolones

23
Q

What is a narrow-spectrum antibiotic?

A

act on only a single or limited group of microorganisms

24
Q

What is an extended spectrum antibiotic?

A

effective against gram (+) and a significant amount of gram (-)

25
Q

What is a broad spectrum antibiotic?

A

affect a wide variety of microbial species and can alter normal flora

26
Q

Describe gram (+) organisms

A

surrounded by peptidoglycan cell wall (85% of eye infections) ex: Staph epidermis and aureus on the skin and strep pneumonia or streptococcus

27
Q

Describe gram (-) organisms

A

cell wall is surrounded by outer membrane. pores prohibit entry of many antibiotics because they need to be hydrophilic to pass through the pores

28
Q

What are the four groups of gram (-) organisms?

A

enterics, haemophilus influenza, neisseria and pseudomonas

29
Q

What organism is a cause of eye infections in adults?

A

staph aureus

30
Q

What organisms is a cause of eye infections in children and old peope?

A

haemophilus influenza

31
Q

Describe anaerobic infections

A

usually composed of mixed gram + and - bacteria, infections occur when bacteria invade poorly oxygenated tissues or tissues that are normally sterile– encased in abscess wall and are foul smelling

32
Q

In general should you select one drug or a combination?

A

one best agent

33
Q

Why is it best to choose a single agent to treat in infection in most cases?

A

reduces possibility of superinfection, decreases resistance, minimizes toxicity

34
Q

What is resistance?

A

bacteria are resistant if the maximal level of the antibiotic that can be tolerated by the host does not halt the bacteria growth

35
Q

Resistance can be either ___ or _____

A

natural or developed

36
Q

What are the two ways resistance are developed?

A

genetic alterations and altered expression of proteins

37
Q

What are spontaneous mutations?

A

insertion, deletion, or substitution alterations in the chromosomal DNA– may be lethal to the cell but if not the mutation will be passed to the progeny

38
Q

What is DNA transfer of resistance?

A

one bacterium may transfer resistance to another by plasmid

39
Q

What are three results of altered expression of proteins?

A

modification of target sites, decreased accumulation, enzymatic inactivation

40
Q

What does modification of a target site do?

A

a change in structure to an antibiotic binding site may produce resistance, often from a mutation

41
Q

What does decreased accumulation do?

A

decreased uptake or increased efflux do not allow the drug to gain access to the site of action of an organism

42
Q

What does enzymatic inactivation do?

A

some bacteria can destroy or inactivate the antimicrobial agent

43
Q

What are prophylactic antibiotics?

A

use of antibiotics for prevention rather than treatment– should be restricted to situations where the benefits outweigh the potential risks because it can result in resistance

44
Q

What is an example of prophylactic treatment that optometrists might use?

A

treatment prior to surgical procedures like cataract surgery

45
Q

T/F since antibiotics are selectively toxic to an invading organism, the host will not have any adverse effects

A

false, still susceptible to adverse effects

46
Q

What are two major complications or antibiotics?

A

direct toxicity and superinfections

47
Q

What is direct toxicity?

A

high concentrations of antibiotics can directly affect host cellular processes ex: aminoglycosides and ototoxicity

48
Q

What are superinfections?

A

alterations in the normal microbial flora that permits overgrowth and the subsequent infections are difficult to treat ex: yeast infection after antibiotics

Systemic Pharm I (13 decks)

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