Module 13: Antimicrobials

If you wanted to determine if a bacterial organism has acquired an antibiotic resistance mechanism, which laboratory test(s) would be most appropriate?

• Run a PCR to test for genes being carried on a plasmid that code for enzymes such as Beta lactamase that are able to inactivate an antibiotic

• Use a special stain that stains the bacterial membrane and examine the cells under the microscope to look for increased membrane permeability

• Sequence the ribosomal RNA of the bacteria to determine if the 50s and 30s subunits have been altered

• Two of the answer choices are correct

• All of the answer choices are correct

What does the concept of selective toxicity rely on? Check all that apply

• Antimicrobials target structures found in microbes but NOT human cells

• Antimicrobials are all effectively broad-spectrum

• Antimicrobials all have to be either antagonistic or synergistic

• Antimicrobials cause greater harm to microbes than their host

Billy falls down and scraps his knee while riding his bike - which of the following should you use to clean the wound and prevent an infection?

• Sterilizer

• Disinfectant

• Pasteruizer

• Antiseptic

Which of the following statements is true regarding antiviral resistance?

• Viruses are capable of acquiring resistance genes via transformation similar to bacteria

• To become resistant to antivirals, a virus can acquire enzymes that will inactivate the antiviral

• Retroviruses are more prone to becoming resistant to antivirals due to a lack of proofreading ability by reverse transcriptase

• To become resistant to antivirals, a virus can alter its metabolic pathways to render the antiviral ineffective

A patient is showing signs of bacterial pneumonia, but you are unsure whether the causative agent is G+ or G-. Which class(es) of antibiotics would be appropriate to prescribe? Check all that apply

• Nucleic Acid Synthesis Inhibitor

• Metabolic Pathway Inhibitor

• Cell Wall Synthesis Inhibitor

• Cell Membrane Inhibitor

In a hospital setting, which type of microbes are likely to be destroyed first by regular means of disinfection?

• Prions

• Mycobacteria

• Gram-negative bacteria

• Enveloped viruses

Choose the correct statement regarding antibiotic resistance

• Physicians should always prescribe antibiotics regardless of if they suspect a patient has a viral vs. bacterial infection to help combat secondary infections

• Bacteriophages/phage therapy is not an appropriate treatment alternative to antibiotics because the therapy targets viral infections

• Patients should only take antibiotics for as long as they are symptomatic and then immediately stop them to prevent antibiotic resistant infections from occurring

• An excellent target for combating the rise of antibiotic resistance would be to utilize fewer antibiotics in agriculture since that is where they are currently most frequently used

If penicillin is administered with erythromycin, it interferes with the mechanism of action of erythromycin. This combination of drugs would therefore be considered

• Synergistic

• Antagonistic

• Broad Spectrum

• Narrow Spectrum

You perform a Gram stain on a patient with a suspected skin infection and obtain the results in the picture. Would antibiotic class would be most appropriate to prescribe the patient and why?

• Metabolic pathway inhibitors because they are broad spectrum and target both G+ and G- bacteria

• Protein synthesis inhibitors because they target the difference in ribosomal structure between G+ and G- cells

• Cell wall synthesis inhibitors because they target the PG layer which G+ cells have more of

• Nucleic acid synthesis inhibitors because they target RNA which is more abundant in G+ cells

Recently a new strain of bird flu (H5N1) has been spreading amongst dairy cows and theres has been a handful of human cases in dairy workers. Given that influenza is a negative sense RNA virus, which type of antiviral would be most appropriate to treat the infected dairy workers?

• Neuraminidase inhibitors

• Integrase inhibitors

• Non-nucleoside reverse transcriptase inhibitors

• DNAse inhibitors