Certified Surgical First Assistant (CSFA) Practice Test

Which antibiotic is a broad-spectrum bactericidal that interferes with cell wall synthesis and is similar to penicillins?

1. Cefazolin

2. Vancomycin

3. Ciprofloxacin

4. Amoxicillin

The correct answer is: Cefazolin

Cefazolin is considered a broad-spectrum bactericidal antibiotic that specifically targets and interferes with bacterial cell wall synthesis, which is a fundamental mechanism for the effectiveness of penicillins as well. The cephalosporin class, which includes cefazolin, shares structural similarities with penicillins, allowing it to exhibit a similar mode of action. By disrupting the synthesis of the bacterial cell wall, cefazolin causes lysis and eventual death of the bacteria, making it a critical choice for prophylactic and therapeutic use in various surgical procedures. In contrast, vancomycin, while also a bactericidal agent, acts primarily against Gram-positive bacteria and has a different mechanism of action, inhibiting cell wall synthesis at a different stage. Ciprofloxacin is a fluoroquinolone that works by inhibiting bacterial DNA gyrase and topoisomerase IV, which is distinct from the mode targeted by penicillins and cephalosporins. Amoxicillin, although it is also a penicillin, is not classified as a broad-spectrum agent in the same way since it has a narrower spectrum compared to cefazolin. Therefore, cefazolin is the fitting choice for the description provided in the question.