Centre for Disease Prevention and Control established a surveillance system for CDI in 34 European countries, whereby an incidence of 5.5 cases per 10,000 patient-days was identified. 5,6 In Latin America, there are only few epidemiological studies on CDI; in a review, Freeman and Bauer 5 reported an incidence ranging from 37 to 84 cases per 10,000 admissions between 2000 and 2005. Mortality due to CDI has also increased: from 2.0 deaths per 100,000 cases in 2007 to 2.3 in 2008, which represents a 15 % increase. 1 In Mexico, Ramírez et al. 7 reported a CDI-associated mortality of 10 % in a private hospital.The risk factors associated with CDI include age > 65 years, 8 neoplasms, diabetes mellitus, chronic kidney disease, immunodeficiency, transplantation, previous exposure to antibiotics, use of chemotherapy, immunosuppressants, proton pump inhibitors and previous gastrointestinal surgery. 3,9 Mortality predictors include age > 65 years, severe infection, organ failure with vasopressor use, need for mechanical ventilation, hyperlactatemia, mental state alterations and absence of vancomycin in patient treatment. 10 Currently, vancomycin and metronidazole are offered as effective drugs for the management of patients with CDI. Timely identification of mortality risk factors will allow early intervention and reduce CDI-attributed mortality. The