Pharm.D. Doctor of Pharmacy Microbiology and Infectious Diseases 1

Question 1

Which antibiotic class inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs)?

Accepted Answer

Beta-lactams

Answer

Beta-lactams (penicillins, cephalosporins, carbapenems) inhibit bacterial cell wall synthesis by covalently binding to penicillin-binding proteins, preventing peptidoglycan cross-linking.

Question 2

What is the primary mechanism of action of fluoroquinolone antibiotics?

Accepted Answer

Inhibit DNA gyrase and topoisomerase IV

Answer

Fluoroquinolones inhibit DNA gyrase and topoisomerase IV, enzymes essential for bacterial DNA replication and transcription, leading to double-strand DNA breaks and cell death.

Question 3

Which organism is the most common bacterial cause of community-acquired pneumonia (CAP) in otherwise healthy adults?

Accepted Answer

Streptococcus pneumoniae

Answer

Streptococcus pneumoniae (pneumococcus) is the most frequently identified bacterial pathogen in community-acquired pneumonia across all age groups.

Question 4

What is the drug of choice for confirmed methicillin-resistant Staphylococcus aureus (MRSA) bacteremia?

Accepted Answer

Vancomycin

Answer

Vancomycin is first-line for MRSA bacteremia because MRSA is resistant to beta-lactams, and vancomycin inhibits cell wall synthesis via a different mechanism (binding D-Ala-D-Ala termini).

Question 5

Which antifungal class inhibits the enzyme lanosterol 14-alpha-demethylase (CYP51), thereby reducing ergosterol synthesis in fungal cells?

Accepted Answer

Azoles (e.g., fluconazole)

Answer

Azoles inhibit lanosterol 14-alpha-demethylase (CYP51), reducing ergosterol synthesis and disrupting fungal cell membrane integrity, resulting in fungistatic activity.

Pharm.D. Doctor of Pharmacy Practice Test

Pharm.D. Doctor of Pharmacy Practice Test

Pharm.D. Doctor of Pharmacy Microbiology and Infectious Diseases 1