Clostridium difficile infection (CDI) has been primarily treated with metronidazole or vancomycin. High recurrence rates, the emergence of epidemic PCR ribotypes (RTs) and the introduction of fidaxomicin in Europe in 2011 necessitate surveillance of antimicrobial resistance and CDI epidemiology. The Clos ER study monitored antimicrobial susceptibility and geographical distribution of C. difficile RTs pre- and post-fidaxomicin...