Principles of antimicrobial therapy Flashcards
H. influenzae’s primary mechanism of antimicrobial resistance is via:
Beta-lactamase production.
The decision-making process where a clinician chooses an agent based on patient characteristics and site of infection is called:
Empiric therapy.
Which of the following best describes the mechanism of action of beta-lactams?
Disrupt synthesis of the peptidoglycan layer of bacterial cell walls
The use of which of the following agents should be avoided in children and pregnant women due to the possibility of teeth staining?
Tetracycline
Which of the following characteristics apply to the macrolides?
Effective against atypical pathogens
Which of the following best describes the mechanism of action of the macrolides?
Inhibition of bacterial protein biosynthesis
Which of the following best describes the mechanism of action of sulfonamides?
Inhibiting folate synthesis
An antibiotic described as having bacteriostatic action is capable of:
Inhibiting growth or reproduction of an organism.
Which of the following antibiotics exhibits time-dependent pathogen-killing activity?
Penicillin
For the minority (<10%) of acute bronchitis cases not caused by virus, the likely causative pathogens include all of the following except:
Haemophilus influenzae.
A 35-year-old woman with a sulfa allergy presents with an uncomplicated UTI. She has not received any systemic antimicrobials in more than 6 months. She is currently not pregnant and is using norelgestromin/ethinyl estradiol patch (Ortho Evra®). You recommend treatment with:
Nitrofurantoin.
The recommended regimen of fosfomycin for the treatment of uncomplicated UTI in a non-pregnant woman is:
One dose of 3 g.
In geographic areas where E. coli resistance to TMP/SMX is >20%, alternative treatments include phenazopyridine plus all of the following except:
Amoxicillin.
Which of the following is a first-line therapy for the treatment of acute bacterial rhinosinusitis in a 9-year-old boy with no risk for antimicrobial resistance?
Amoxicillin-clavulanate
A 46-year-old man who is currently smoking 1 PPD and has a 30 pack-year cigarette smoking history with penicillin allergy presents with acute bacterial rhinosinusitis. Three weeks ago, he was treated with a macrolide for “bronchitis.” You now prescribe:
Levofloxacin.
A 35-year-old woman who is not pregnant was initiated on high-dose amoxicillin 4 days ago to treat acute bacterial rhinosinusitis. She returns complaining of no change in symptoms. You recommend switching her treatment to:
Levofloxacin.
A 26-year-old woman presents with uncomplicated UTI. She is otherwise healthy, has not received any systemic antimicrobials in the past year, does not have a sulfa allergy, and is not taking any medications other than Ortho-Cyclen® (ethinyl estradiol and norgestimate) for birth control. Her last menstrual period began 10 days ago. The local E. coli resistance rate to TMP/SMX is about 10%. The preferred therapy for this patient is:
Trimethoprim-sulfamethoxazole.
A 13-year-old boy presents with acute bacterial rhinosinusitis. He has a beta-lactam allergy and had taken clarithromycin 2 months ago for a “bad cold.” You recommend treatment with:
Levofloxacin.
Risk factors for developing fluoroquinolone-associated tendinitis and tendon rupture include all of the following except:
Recent use of a systemic beta-lactam antimicrobial.
All of the following antimicrobials would be expected to exhibit in vitro activity against beta-lactamase-producing Moraxella catarrhalis except:
Amoxicillin
