What is the recommended first-line therapy for mild-to-moderate C. difficile infection in adults?

What is the recommended first-line therapy for mild-to-moderate C. difficile infection in adults?

• A. Oral vancomycin or fidaxomicin
• B. Metronidazole
• C. Amoxicillin-clavulanate
• D. Ciprofloxacin

Answer: (A)

The main idea is to use an antibiotic that treats C. difficile effectively in the gut while lowering the risk of relapse in mild-to-moderate cases. Oral vancomycin and fidaxomicin fit this goal best because they achieve strong cure rates in the colon. Fidaxomicin, in particular, has the added advantage of reducing recurrence in many patients, and vancomycin remains highly effective with a well-established regimen. Metronidazole used to be considered first-line, but it is now regarded as less effective for initial therapy and is associated with higher relapse rates, so it’s not preferred. Amoxicillin-clavulanate and ciprofloxacin are not appropriate treatments for C. difficile infection themselves; they may contribute to gut disruption and do not reliably resolve the infection. A typical first-line course is oral vancomycin or fidaxomicin for about 10 days.

The main idea is to use an antibiotic that treats C. difficile effectively in the gut while lowering the risk of relapse in mild-to-moderate cases. Oral vancomycin and fidaxomicin fit this goal best because they achieve strong cure rates in the colon. Fidaxomicin, in particular, has the added advantage of reducing recurrence in many patients, and vancomycin remains highly effective with a well-established regimen. Metronidazole used to be considered first-line, but it is now regarded as less effective for initial therapy and is associated with higher relapse rates, so it’s not preferred. Amoxicillin-clavulanate and ciprofloxacin are not appropriate treatments for C. difficile infection themselves; they may contribute to gut disruption and do not reliably resolve the infection. A typical first-line course is oral vancomycin or fidaxomicin for about 10 days.