The investigators' study is an open-label randomized controlled trial, enrolling patients with recurrent C. difficile infection, who are candidates for further antibiotic treatment in accordance with guidelines. Recurrent C. difficile infection is meant as the reappearance of clinical symptoms and positivity of C. difficile toxin test within 8 weeks after the end of the previous therapy. Patients' stool will be screened for detection of parasites and enteric bacterial pathogens to exclude other infective pathogens. Patients with severe clinical features (sepsis, severe dehydration, major co-morbidities), former colectomy, high-risk of endoscopic complications, inflammatory bowel diseases (IBD), irritable bowel syndrome (IBS), viral hepatitis, AIDS or syphilis will be excluded.