Question 1

If a microbe has developed resistance to a certain antimicrobial preparation,the prescriber should:&#10;A) increase the frequency of the dose of the antimicrobial.&#10;B) increase the dose of the antimicrobial.&#10;C) determine which antimicrobial the microbe may be sensitive to.&#10;D) prescribe topical preparations only.

Accepted Answer

If a microbe has developed resistance to a certain antimicrobial preparation, the best course of action for the prescriber is to determine which antimicrobial(s) the microbe may be sensitive to. This will allow for the selection of a more appropriate and effective antimicrobial for treating the infection, rather than increasing the dose or frequency of an ineffective antimicrobial or limiting treatment options to only topical preparations.

Question 2

An example of an antibacterial agent that attacks the cell wall is:&#10;A) nitrofurantoin.&#10;B) tetracycline.&#10;C) neomycin.&#10;D) penicillin.

Accepted Answer

Penicillin is an example of an antibacterial agent that attacks the cell wall. It works by inhibiting the formation of peptidoglycan, a crucial component of bacterial cell walls. Without a strong cell wall, bacteria are unable to maintain their shape and eventually rupture, leading to their death.

Question 3

Which of the following is NOT a likely cause of antimicrobial resistance?&#10;A) Using narrow-spectrum antibiotics instead of broad-spectrum antibiotics&#10;B) Excessive use of antibiotics in animals bred for human consumption&#10;C) Failure to conform to the dosing regime&#10;D) Spraying excess antibiotic in the air after drawing it up for injection

Accepted Answer

Using narrow-spectrum antibiotics is less likely to contribute to antimicrobial resistance compared to broad-spectrum antibiotics because they target specific pathogens rather than a wide range of organisms, reducing the pressure on bacteria to develop resistance.

Question 4

Which of the following antimicrobial agents inhibits DNA replication?&#10;A) Linezolid&#10;B) Mupirocin&#10;C) Colistin&#10;D) Norfloxacin

Accepted Answer

Norfloxacin is a fluoroquinolone antibiotic that inhibits bacterial DNA replication by targeting DNA gyrase and topoisomerase IV enzymes.

Question 5

An antimicrobial agent with a narrow spectrum of activity reflects a drug that has:&#10;A) only a weak antibiotic action.&#10;B) effectiveness against a relatively small number of microbes.&#10;C) a low potency.&#10;D) a narrow margin of safety.

Accepted Answer

An antimicrobial agent with a narrow spectrum of activity is effective against only a relatively small number of microbes, as opposed to broad-spectrum antimicrobial agents which cover a wider range of microbes. Therefore, option B is the correct choice.

Question 6

Which of the following antimicrobial agents has a dose-dependent activity on microorganisms?&#10;A) The glycoprotein vancomycin&#10;B) The glycoprotein teicoplanin&#10;C) The penicillin amoxycillin&#10;D) The aminoglycoside gentamicin

Accepted Answer

Aminoglycosides like gentamicin exhibit dose-dependent killing, meaning that the higher the dose, the greater the bacterial killing effect. Vancomycin and teicoplanin are both glycopeptide antibiotics that do not exhibit dose-dependent killing, while amoxycillin is a beta-lactam antibiotic that also does not exhibit dose-dependent killing.

Question 7

The actions of streptomycin and amikacin:&#10;A) are considered first-line agents for tuberculosis.&#10;B) are ineffective for the bactericidal phase.&#10;C) interfere with protein synthesis.&#10;D) are best mediated by the oral route.

Accepted Answer

Streptomycin and amikacin both interfere with bacterial protein synthesis, making them effective antibiotics against a variety of bacterial infections. They are often used as second-line agents for tuberculosis, after initial treatment with first-line agents such as isoniazid and rifampin. These antibiotics are most often given via injection, rather than orally. They are effective in both the bactericidal and bacteriostatic phases of bacterial growth.

Question 8

An antimicrobial drug mechanism of action generally regarded as bacteriostatic is one that:&#10;A) interferes with metabolic processes.&#10;B) inhibits cell wall synthesis.&#10;C) promotes protein synthesis.&#10;D) disrupts cell membranes.

Accepted Answer

Antimicrobial drugs that interfere with metabolic processes are generally regarded as bacteriostatic. This means that they inhibit bacterial growth rather than killing the bacteria outright. Examples of such drugs include sulfonamides and tetracyclines. In contrast, drugs that inhibit cell wall synthesis, promote protein synthesis, or disrupt cell membranes are generally regarded as bactericidal, meaning that they kill the bacteria rather than just inhibiting growth.

Question 9

Which one of the following statements is relevant regarding antimicrobial drugs that are time-dependent?&#10;A) It is important to measure peak and trough plasma concentrations.&#10;B) The plasma drug concentration must be 60% of the maximum effective concentration for it to be effective.&#10;C) An increase in dose will result in an increased effect.&#10;D) The period above the minimum effective concentration determines the effectiveness of treatment.

Accepted Answer

For time-dependent antimicrobial drugs, the period above the minimum effective concentration (MEC) determines the effectiveness of treatment. The goal is to maintain drug concentration above the MEC for a certain duration of time to properly treat the infection. Peak and trough levels are not typically monitored for time-dependent drugs, and an increase in dose may not necessarily result in an increased effect. Therefore, options A, B, and C are not relevant for time-dependent antimicrobial drugs.

Question 10

It is recommended that surgical prophylaxis with antibiotics is not undertaken with a:&#10;A) mastectomy.&#10;B) coronary bypass surgery.&#10;C) splenectomy.&#10;D) large bowel resection.

Accepted Answer

Surgical prophylaxis with antibiotics is not recommended for mastectomy because it is a clean procedure and the risk of infection is low.

Question 11

Individuals with antibiotic-associated colitis should be treated with:&#10;A) codeine.&#10;B) cholestyramine.&#10;C) loperamide.&#10;D) tetracycline.

Accepted Answer

The answer of Individuals with antibiotic-associated colitis should be treated...

Question 12

Which anti-infective agent would have the highest risk if used in pregnancy?&#10;A) Selected penicillins&#10;B) Nystatin&#10;C) Amphotericin&#10;D) Nitrofurantoin

Accepted Answer

The answer of Which anti-infective agent would have the highest...

Deck 67: Introduction to Chemotherapy