Principles of Anti-INfective Therapy Flashcards Preview

Microbiology Exam I > Principles of Anti-INfective Therapy > Flashcards

Flashcards in Principles of Anti-INfective Therapy Deck (38)
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1
Q

Chemotherapeutic agents

A

any drug used to treat illness or disease, infectious disease generally refers to antibiotics

2
Q

Antimicrobial agent

A

substance that interferes with the proliferation of microorganisms

3
Q

Antibiotics agent

A

antimicrobial activity whose source is “natural” living organisms

4
Q

Antimicrobial spectrum - Bacteristatic

A

antimicrobial agent that inhibits growth when present, but does not kill; reversible; relies on immune system to eliminate pathogen

5
Q

Bactericidal

A

Agents that kill pathogen, but do not eliminate the dead cells/viruses; irreversible

6
Q

Narrow spectrum antibiotics

A

antibiotics that target a narrow range of microorganisms

7
Q

Broad spectrum antibiotics

A

antibiotics effective in killing both gram (+) and gram(-) bacteria, not preferred bc it wipes out NF and may lead to superinfections

8
Q

Resistant

A

microorganisms that are NOT inhibited

9
Q

Sensitive

A

microorganisms that are ARE inhibited

10
Q

Kirby-Bauer Disc diffusion Assay

A

antimicrobial sensitivity test to determine if the particular pathogen is sensitive or resistant to a specific antibiotic by measuring the zone of growth inhibition

11
Q

Kirby-Bauer Disc diffusion Assay down-side

A

cannot distinguish between bacteristatic and bactericidal, qualitative test

12
Q

Minimum Inhibitory Concentration (MIC) test

A

antimicrobial susceptibility test to measure the minimal concentration of antibodies necessary to inhibit the growth of microorganisms

13
Q

Minimum Inhibitory Concentration (MIC) test down-side

A

cannot distinguish between bacteristatic and bactericidal, quantitative test

14
Q

Minimum Bactericidal Concentration (MBC) test

A

antimicrobial susceptibility test to measure least amount of antibiotics to KILL 99.9% of the microorganism, MICs are grown on agar plates to determine if they were killed or inhibited by the antibiotics

15
Q

MBC =

A

most diluted MIC that did not have growth after plating on agar

16
Q

Dosage of antibiotics should ___________ the MBC and MIC

A

exceed

17
Q

Antimicrobial serumcidal concentrations

A

antimicrobial susceptibility test to measure the lowest concentration of antibiotics needed to kill microorganism in the presence of patient’s serum

18
Q

Antibiogram

A

detailed account of a hospitals trends of antibiotic usage, in comparison to resistance and susceptibility patterns

19
Q

Antibiogram can help prevent

A

antibiotic resistance by alleviating pressures

20
Q

Poor Selective Toxicity

A

target is more similar to self, drugs that target cell membrane exhibit poor selectivity - harmful to patient and microbe

21
Q

Good Selective Toxicity

A

target is less similar to self, drugs that target peptidoglycan cell walls exhibit good selectivity - harmful to microbe not to patient

22
Q

Why abscess formation is difficult to treat…

A

poor blood flow, difficult to deliver drugs/antibodies, multiply slower and are less effected by drugs, phagocytes do not reach site, tissue necrosis releases nutrients needed for bacterial growth, low pH at site effects drug effectiveness

23
Q

Treating an abscess

A

drainage and removal of necrotic tissue

24
Q

Why foreign bodies allow growth of microorganisms..

A

biofilms are allowed to grow on foreign objects, they should be removed ASAP

25
Q

Immunosuppression

A

even with antimicrobials, an intact immune system is necessary for removal of debris and effective treatment

26
Q

Superinfect

A

treat one disease and a new and different disease develops, generally as a result of overgrowth of NF

27
Q

Location of infection

A

antibiotics can penetrate tissues differently, must be considered when prescribing a medication

28
Q

Chemoprophylaxis

A

administering an antimicrobial to a patient who is not infected but at increased risk

29
Q

Justified prophylaxis

A

erythromycin eye drops to prevent opthalmia neonatorium, prophylaxis against malaria in travelers, rheumatic heart disease patients to prevent strep, bowel surgery, recurrent UTI, bite wound, exposure to meningococcal meningitis, MTB, HIV

30
Q

Unjustified prophylaxis

A

prevent secondary bacterial pneumonia in viral respiratory case, clean surgery, because patient insists

31
Q

Synergism (2 antimicrobials)

A

when used in conjunction with one another are much stronger (cidal) than separately

32
Q

Additive

A

when used in conjunction with one another they are additive in nature 1 + 1 = 2

33
Q

Antagonism

A

when used together, they reduce the effectiveness in comparison to being separate (drug/drug interaction or competition)

34
Q

Indifference

A

drugs used in conjunction has no effect on one another

35
Q

When to use combination therapy

A

polymicrobic infection, to lower dose of toxic drug, increase cidal effect, treat life-threatening illness, prevent emergence of resistance (TB, HIV)

36
Q

Drug resistance mechanisms - altering target

A

alter binding proteins, alter DNA gyrase, alter expression of dehydrofolate reductase

37
Q

Drug resistance mechanisms - inactivation of drug

A

ability to hydrolyze and breakdown drug, circumvent drug action by acquiring a different enzyme with same function (beta-lactamase)

38
Q

Drug resistance mechanisms - tolerance

A

evasion of killing by depression of bacterial growth rate