Professional and Linguistic Assessments Board (PLAB) Practice Exam

What is a standard treatment for Clostridium difficile infection?

1. Amoxicillin

2. Ciprofloxacin

3. Metronidazole

4. Vancomycin

The correct answer is: Metronidazole

In the context of treating Clostridium difficile infection (CDI), metronidazole has been historically one of the standard treatments, especially for mild to moderate cases. It works effectively against the anaerobic bacteria, targeting their metabolic processes. In the past, it was frequently utilized as the first-line agent for initial episodes of CDI. However, it’s essential to acknowledge that clinical guidelines have evolved, and while metronidazole remains an option, vancomycin is currently preferred for both initial and recurrent episodes due to its higher cure rates and lower recurrence rates. This shift reflects the increasing recognition of CDI's pathogenicity and the potential for metronidazole resistance. Amoxicillin and ciprofloxacin are not typically used for CDI because they lack effective activity against C. difficile. Amoxicillin is related to penicillin antibiotics that are ineffective against this particular infection, while ciprofloxacin, a fluoroquinolone, is also not considered effective for treating CDI. Therefore, metronidazole is recognized for its historical standard use, although current practice may favor vancomycin as a first-line treatment in many cases.