American Board of Internal Medicine (ABIM) Certification Practice Exam

What is the first-line treatment for diarrhea caused by Campylobacter?

1. Amoxicillin

2. Ciprofloxacin

3. Azithromycin or erythromycin

4. Metronidazole

The correct answer is: Azithromycin or erythromycin

The first-line treatment for diarrhea caused by Campylobacter is azithromycin or erythromycin. These antibiotics are particularly effective against Campylobacter species, which can cause gastrointestinal symptoms, including diarrhea. Azithromycin is often preferred due to its convenient dosing regimen and its effectiveness in treating Campylobacter infections, especially in cases where the patient may be pregnant or when there's a need for oral therapy. Erythromycin is also effective; however, it can have gastrointestinal side effects, which may limit its use in some patients. While other antibiotics, such as ciprofloxacin, can be used in the treatment of Campylobacter infections, resistance has been increasing, which diminishes their effectiveness. Therefore, the choice of azithromycin or erythromycin addresses both efficacy and bacterial resistance concerns, making it the recommended first-line treatment in clinical practice. In summary, the appropriateness of azithromycin or erythromycin for Campylobacter-associated diarrhea is supported by their therapeutic efficacy, safety profile, and the context of rising resistance to alternative treatments.