Antimicrobials

Question 1

Why do we administer antimicrobials in combinations?

Answer 1

Obtain antimicrobial synergism

Treat polymicrobial infections

Decrease the emergence of resistance

Reduce drug toxicity

Question 2

Beta Lactams and Aminoglycosides given together to give a ____________ effect.

Answer 2

Beta Lactams and Aminoglycosides given together to give a synergistic effect.

Question 3

Classes of antimicrobials that act on the cell wall/ cell membrane

Answer 3

Beta Lactams

Glycopeptides

Bacitracin

Polymyxin

Question 4

Types of antimicrobial resistance

Answer 4

Innate Resistance

Acquired Resistance

Question 5

Mechanism of action of antimetabolite antifungal drugs

Answer 5

Act as an inhibitor of both DNA and RNA synthesis

Question 6

Examples of natural antibiotics

Answer 6

Streptomycin

Penicillin

Tetracycline

Question 7

Semi-Synthetic Antibiotics

Answer 7

Chemically altered natural compound

Question 8

Antimicrobial

Answer 8

Drugs that destroy microbes, prevent their multiplication or growth or prevent their pathogenic effect

Question 9

Susceptibility result - R

Answer 9

High likelihood of therapeutic failure

Question 10

Bacteriostatic

Answer 10

Inhibit bacteria

Question 11

Susceptibility result - S

Answer 11

High likelihood of therapeutic success

Question 12

Factors to consider in antimicrobial therapy

Answer 12

Cost

Safety

Ease of Use

Possible Emergence of Resistance

Question 13

Classes of antimicrobials that act on protein synthesis

Answer 13

Tetracyclines

Macrolides

Aminoglycosides

Chloramphenicol

Lincosamides

Streptogramins

Question 14

Mechanism of action of polyene antifungal drugs

Answer 14

Interact with sterols in the cell membrane

Question 15

Susceptibility Break Point

Answer 15

Drug concentration above which an organism is considered resistant and at or below this value organism is susceptible to the drug

Question 16

Tetracycline is a ________ spectrum antibiotic

Answer 16

Tetracycline is a broad spectrum antibiotic

Question 17

Acquired Resistance

Answer 17

Acquired resistance by mutation or horizontal gene transfer

Question 18

Bacteriocidal

Answer 18

Kills bacteria

Question 19

Alexander Fleming

Answer 19

Discovered penicillin

Question 20

To proceed with antimicrobial treatment, the veterinarian should know

Answer 20

Location of the infection

Likely pathogen

Antimicrobials effective against particular pathogen in particular site

Question 21

Antimicrobial Agent

Answer 21

Chemical substance derived from a biological source or produced by a cheical synthesis that kills or inhabits the growth of microorganisms

Question 22

Susceptibility result - I

Answer 22

Uncertain therapeutic outcome

Question 23

Examples of synthetic antibiotics

Answer 23

Sulfonamide

Enrofloxacin

Marbofloxacin

Question 24

Examples of semi-synthetic antibiotics

Answer 24

Ampicillin, Amikacin

Question 25

Classes of antimicrobials that act on nucleic acid synthesis

Answer 25

Sulfonamides/Trimethoprim Nitroimidazoles/ Nitrofurans Fluroquinolones Novobiocin Rifampin

Question 26

Classification of Antimicrobial agents is based on

Answer 26

Chemical family structure Mode of action Type of antimicrobial activity Spectrum of antimicrobial activity

Question 27

Innate Resistance

Answer 27

Pre-existing genomic property that causes resistance

Question 28

Examples of Antifungal Drugs

Answer 28

Polyens Azoles

Question 29

Three break point values are

Answer 29

Susceptible Intermediate Resistant

Question 30

Natural (True) Antibiotics

Answer 30

Produced by bacteria or fungus

Question 31

Antibiotic

Answer 31

Chemical substance produced by a microorganism that inhabits the growth of or kills other microorganisms

Question 32

Pharmacodynamics

Answer 32

Effect of the drug on the body, mechanism of action and efficacy

Question 33

Synthetic Antibiotics

Answer 33

Chemically designed in the lab

Question 34

Disk Diffusion (Kirby Bauer)

Answer 34

Bacterial isolate in pure culture Spread on agar plate Single-concentration antimicrobial disks used Growth inhibition zone diameter measured Compared to published reference break points

Question 35

Mechanism of action of azole antifungal drugs

Answer 35

Inhibit cytochrome P450 dependent enzymes involved in the biosynthesis of ergosterol

Question 36

Antifungal drugs target \_\_\_\_\_\_\_\_.

Answer 36

Antifungal drugs target **ergosterols**.

Question 37

Narrow Spectrum Antibiotic

Answer 37

Affect only a narrow range of bacteria

Question 38

Minimum Inhibitory Concentration (MIC)

Answer 38

Minimum amount of drug required to inhibit bacterial growth

Question 39

Mechanisms of Resistance

Answer 39

Enzymatic destruction or inactivation Prevention of penetration to target sites within microbe Alteration of drug target site Rapid efflux of antibiotics

Question 40

Penicillin is a _________ spectrum antibiotic

Answer 40

Penicillin is a **narrow** spectrum antibiotic

Question 41

Pharmacokinetics

Answer 41

Fate of the drug in the body \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ Absorption, Transformation, Distribution and Elimination

Question 42

Broad Spectrum Antibiotic

Answer 42

Active against a wide variety of bacteria

Question 43

Mechanism of action of allyamine and morpholine antifungal drugs

Answer 43

Inhibit ergosterol biosynthesis

Question 44

Broth Dilution

Answer 44

Multiple dilutions of antimicrobial agents Published reference breakpoints to interpret Measure and report growth inhibition endpoint