1.
Which of the following fluoroquinolones cannot be used for a UTI?
Correct Answer
C. Moxifloxacin
Explanation
Among the fluoroquinolones, moxifloxacin is the agent with the least penetration into urine
2.
Which of the following fluoroquinolones displays slight activity against Pseudomonas aeruginosa?
Correct Answer
D. Cipro and Levo
Explanation
Ciprofloxacin and Levofloxacin both display slight activity against Pseudomonas aeruginosa. These fluoroquinolones belong to the same class of antibiotics and have similar mechanisms of action. They inhibit the DNA gyrase and topoisomerase IV enzymes, which are essential for bacterial DNA replication and repair. Pseudomonas aeruginosa is a gram-negative bacterium that can cause severe infections, especially in immunocompromised individuals. While Ciprofloxacin and Levofloxacin are not the first-line treatment for Pseudomonas aeruginosa infections, they can still provide some activity against this pathogen. Moxifloxacin, on the other hand, does not have significant activity against Pseudomonas aeruginosa.
3.
Which of the following agents is MRSA most likely to be resistant to?
Correct Answer
B. Clindamycin
Explanation
MRSA (Methicillin-resistant Staphylococcus aureus) is most likely to be resistant to Clindamycin. This is because MRSA is known to have high resistance rates to Clindamycin, making it less effective in treating MRSA infections. Vancomycin, Bactrim, Linezolid, and Doxycycline are still considered effective against MRSA, although resistance to these agents can also occur.
4.
Describe the killing characteristic of vancomycin
Correct Answer
C. Bacteriostatic or bactericidal
Explanation
Vancomycin is a broad-spectrum antibiotic that is commonly used to treat serious bacterial infections. Its killing characteristic can be described as bacteriostatic or bactericidal. Bacteriostatic drugs inhibit the growth and reproduction of bacteria, allowing the immune system to eliminate them. Bactericidal drugs, on the other hand, directly kill bacteria. In the case of vancomycin, it can exhibit both bacteriostatic and bactericidal effects depending on the concentration and specific bacteria being targeted. At lower concentrations, it is bacteriostatic, while at higher concentrations, it is bactericidal.
5.
Describe the killing characteristic of vancomycin
Correct Answer
A. Time-dependent
Explanation
Vancomycin is a time-dependent antibiotic, meaning that its effectiveness in killing bacteria is dependent on the duration of time that the drug concentration remains above the minimum inhibitory concentration (MIC). This means that maintaining a therapeutic level of vancomycin in the body for a longer period of time is more important than achieving a high peak concentration. Concentration-dependent antibiotics, on the other hand, rely on achieving a high peak concentration to effectively kill bacteria. Therefore, the correct answer is "Time-dependent."
6.
What indication DOES NOT have a vancomycin-associated trough of 15-20 mcg/mL?
Correct Answer
C. Cellulitis
Explanation
Cellulitis does not have a vancomycin-associated trough of 15-20 mcg/mL. This means that maintaining a vancomycin trough level within this range is not necessary or effective in treating cellulitis. The other conditions listed, such as meningitis, pneumonia, osteomyelitis, and endocarditis, may require vancomycin therapy with a target trough level of 15-20 mcg/mL for optimal treatment outcomes.
7.
Which of the following agents is bound by pulmonary surfactant?
Correct Answer
A. Daptomycin
Explanation
Daptomycin is the correct answer because it is a lipopeptide antibiotic that binds to the bacterial cell membrane and disrupts its function. Pulmonary surfactant is a mixture of lipids and proteins that reduces surface tension in the lungs and prevents alveolar collapse. Daptomycin's lipophilic nature allows it to bind to the lipids in pulmonary surfactant, potentially affecting its function.
8.
Which of the following antimicrobials has the greatest potential to interact with warfarin?
Correct Answer
E. All of the above
Explanation
All of the above antimicrobials (Bactrim, Fluconazole, and Metronidazole) have the potential to interact with warfarin. Warfarin is a blood thinner that works by inhibiting vitamin K-dependent clotting factors. These antimicrobials can interfere with the metabolism of warfarin, leading to an increased risk of bleeding. Bactrim contains sulfamethoxazole and trimethoprim, which can enhance the effects of warfarin. Fluconazole can inhibit the metabolism of warfarin, leading to increased levels of the drug in the body. Metronidazole can also inhibit the metabolism of warfarin and increase its effects. Therefore, all of these antimicrobials have the potential to interact with warfarin.
9.
Which of the following agents is the WORST choice to treat CAP?
Correct Answer
C. Ciprofloxacin
Explanation
Ciprofloxacin is the worst choice to treat CAP because it is a fluoroquinolone antibiotic, which is not recommended as a first-line treatment for community-acquired pneumonia (CAP). Fluoroquinolones are generally reserved for more severe cases or when other treatment options have failed due to their potential for serious side effects, such as tendon rupture and Clostridium difficile infection. Therefore, other agents like Zosyn, Doxycycline, or Augmentin would be preferred over Ciprofloxacin for the treatment of CAP.
10.
An appropriate response to treating Vancomycin-induced Red Man Syndrome would be:
Correct Answer
E. All of the above
Explanation
All of the above options are appropriate responses to treating Vancomycin-induced Red Man Syndrome. Diphenhydramine is an antihistamine that can help alleviate the symptoms of the syndrome, while acetaminophen can be used to relieve any associated pain or discomfort. Slowing the infusion rate on subsequent infusions can also help prevent the syndrome from occurring or reduce its severity. Therefore, using all of these options together can provide comprehensive treatment for Vancomycin-induced Red Man Syndrome.
11.
Aspiration pneumonia treatment requires additional coverage of what organisms?
Correct Answer
A. Anaerobes
Explanation
Aspiration pneumonia is a type of lung infection that occurs when foreign material, such as food, drink, or saliva, is inhaled into the lungs. Anaerobes are bacteria that can cause infection in the absence of oxygen, and they are commonly associated with aspiration pneumonia. Therefore, treatment for aspiration pneumonia should include coverage for anaerobic organisms to effectively treat the infection.
12.
Which of the following is not an option when treating C diff colitis?
Correct Answer
C. IV Vancomycin
Explanation
IV Vancomycin is not an option when treating C diff colitis because vancomycin is not effective when administered intravenously. Vancomycin is only effective when given orally, as it needs to reach the colon to treat the infection. IV Metronidazole and PO Metronidazole are both options for treating C diff colitis, as metronidazole can be given intravenously or orally. Similarly, PO Vancomycin is also a valid treatment option, as it can be administered orally to target the infection in the colon.
13.
Which aminoglycoside has less sites available for modification, and thus additional coverage of otherwise AG-resistant pathogens?
Correct Answer
C. Amikacin
Explanation
Amikacin has less sites available for modification compared to other aminoglycosides. This means that it is less susceptible to resistance mechanisms used by bacteria to modify and inactivate aminoglycosides. As a result, amikacin has additional coverage against pathogens that are resistant to other aminoglycosides.
14.
What is the most common mechanism of resistance found in Pseudomonas aeruginosa?
Correct Answer
A. Many efflux pumps
Explanation
Pseudomonas aeruginosa is known for its ability to develop resistance to multiple antibiotics. One of the most common mechanisms of resistance found in this bacterium is the presence of many efflux pumps. Efflux pumps are proteins that actively pump out antibiotics from the bacterial cell, preventing them from reaching their target and exerting their effect. The presence of multiple efflux pumps allows Pseudomonas aeruginosa to effectively expel a wide range of antibiotics, making it highly resistant to treatment.
15.
What is the proper dose of azithromycin for MAC prophylaxis in AIDS patients?
Correct Answer
C. 1200 mg weekly
Explanation
The proper dose of azithromycin for MAC prophylaxis in AIDS patients is 1200 mg weekly. This dosage is effective in preventing the development of Mycobacterium avium complex (MAC) infections in individuals with AIDS.
16.
Which of the following agents has a potential to cause thrombocytopenia, chiefly correlated with use greater than 28 days?
Correct Answer
E. Linezolid
Explanation
Linezolid is a potential agent that can cause thrombocytopenia, especially when used for more than 28 days. Thrombocytopenia refers to a condition where there is a low platelet count in the blood, which can lead to an increased risk of bleeding. Linezolid is an antibiotic that is commonly used to treat infections caused by certain bacteria. It works by inhibiting the growth of bacteria. However, prolonged use of linezolid can have adverse effects on platelet production, leading to thrombocytopenia.
17.
What is the most relevant pathogen that tigecycline lacks coverage of?
Correct Answer
A. Pseudomonas aeuruginosa
Explanation
Tigecycline lacks coverage of Pseudomonas aeruginosa, which means that it is not effective against this specific pathogen. This suggests that tigecycline may not be the best choice for treating infections caused by Pseudomonas aeruginosa. It is important to consider alternative antibiotics that have better coverage for this particular pathogen in order to ensure effective treatment.
18.
Levofloxacin has a boxed warning concerning:
Correct Answer
D. Tendon rupture
Explanation
Levofloxacin has a boxed warning concerning tendon rupture. This means that there is a significant risk of tendon rupture associated with the use of this medication. Patients who are prescribed levofloxacin should be aware of this potential side effect and should be monitored closely for any signs of tendon pain or weakness. If these symptoms occur, patients should stop taking the medication and seek medical attention immediately. Tendon rupture can be a serious and debilitating condition, so it is important for patients and healthcare providers to be aware of this risk.
19.
Ciprofloxacin has a category X drug interaction with which of the following agents?
Correct Answer
A. Tizanidine
Explanation
Ciprofloxacin has a category X drug interaction with Tizanidine. This means that the combination of these two drugs can cause significant harm to the patient and should be avoided. Category X interactions are the most severe type of drug interaction, indicating that the risks outweigh the benefits and the combination should be avoided if possible. It is important for healthcare professionals to be aware of these interactions in order to prevent potential harm to patients.
20.
How many oral agents exist that could effectively treat MRSA as monotherapy?
Correct Answer
B. 4
Explanation
Doxycycline, clindamycin, bactrim, linezolid
21.
Which of the following agents has the greatest potential for causing C diff colitis?
Correct Answer
C. Clindamycin
Explanation
Clindamycin has the greatest potential for causing C diff colitis. This is because clindamycin is known to disrupt the normal balance of bacteria in the gut, allowing for the overgrowth of Clostridium difficile (C diff) bacteria. C diff colitis is an infection of the colon caused by this bacteria, and it can lead to severe diarrhea, abdominal pain, and inflammation of the colon. While other agents listed may also have the potential to cause C diff colitis, clindamycin is specifically known for its strong association with this infection.
22.
What is the purpose of cilastin in Primaxin?
Correct Answer
B. Prevent a toxicity of imipenem
Explanation
Cilastin prevents renal tubular necrosis
23.
What additional pathogen is not a typical finding in osteomyelitis, but appears as a possibility in patients who admit to IV drug use?
Correct Answer
B. Pseudomonas aeruginosa
Explanation
Pseudomonas aeruginosa is not a typical finding in osteomyelitis but may appear as a possibility in patients who admit to IV drug use. This is because Pseudomonas aeruginosa is a common pathogen associated with infections in IV drug users, including osteomyelitis. IV drug use can introduce this pathogen into the bloodstream, which can then lead to bone infections such as osteomyelitis. Therefore, Pseudomonas aeruginosa is a potential additional pathogen to consider in patients with a history of IV drug use and suspected osteomyelitis.