Microbiology and Infectious Diseases Flashcards
7 cards from real Pharm.D. Doctor of Pharmacy practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Microbiology and Infectious Diseases flashcards as text
Which antibiotic is the preferred first-line agent for uncomplicated urinary tract infections (UTIs) in non-pregnant women per current IDSA guidelines?
Answer: Nitrofurantoin
Nitrofurantoin (Macrobid) is a preferred first-line agent for uncomplicated UTIs due to its high urinary concentrations, efficacy against common uropathogens, and minimal collateral ecological effects.
What is the bactericidal mechanism of action of penicillin on susceptible bacteria?
Answer: Inhibits transpeptidation, preventing peptidoglycan cross-linking and causing osmotic lysis
Penicillin inhibits transpeptidase enzymes (penicillin-binding proteins), preventing the cross-linking of peptidoglycan strands, resulting in structural weakness of the cell wall and osmotic lysis.
Which antifungal agent causes nephrotoxicity with renal tubular acidosis and electrolyte wasting (potassium, magnesium), requiring frequent laboratory monitoring during therapy?
Answer: Amphotericin B deoxycholate
Amphotericin B deoxycholate (conventional formulation) is notorious for nephrotoxicity, causing azotemia, distal renal tubular acidosis, and urinary wasting of potassium and magnesium.
Which laboratory method is the gold standard for confirming a diagnosis of active pulmonary tuberculosis?
Answer: Sputum acid-fast bacilli (AFB) culture with drug susceptibility testing
Sputum AFB culture with drug susceptibility testing is the gold standard, as it confirms viable M. tuberculosis organisms and provides critical information on drug resistance patterns to guide treatment.
Per 2022 ACIP recommendations, what is the preferred pneumococcal vaccination strategy for immunocompetent adults aged 65 years and older who have never received a pneumococcal vaccine?
Answer: PCV15 followed by PPSV23, or PCV20 alone
ACIP 2022 guidelines recommend PCV15 (Vaxneuvance) followed by PPSV23 at least 1 year later, or PCV20 (Prevnar 20) alone, replacing the older PCV13+PPSV23 sequential strategy.
What is the drug of choice for treating Rocky Mountain spotted fever (RMSF) caused by Rickettsia rickettsii, including in pediatric patients?
Answer: Doxycycline
Doxycycline is the drug of choice for RMSF regardless of patient age; the mortality risk of untreated or undertreated RMSF far outweighs the minimal risk of dental staining from a short treatment course.
Which antibiotic class inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit and blocking aminoacyl-tRNA from entering the ribosomal A site (bacteriostatic)?
Answer: Tetracyclines
Tetracyclines bind reversibly to the 30S ribosomal subunit and block aminoacyl-tRNA attachment to the A site, halting protein synthesis in a bacteriostatic, concentration-independent manner.