Metronidazole in the prevention of antibiotic-associated diarrhoea and Clostridium difficile infection in high-risk hospitalised patients

Abstract

Abstract Background In-hospital diarrhoea has a high impact on morbidity and mortality rates among hospitalised patients. Chemoprophylaxis with antibiotics in selected patients could be a cost-effective tool for prevention. Methods A prospective randomised, open-label study was conducted in a tertiary hospital in Mexico City, selecting patients at high risk of acquiring in-hospital diarrhoea and assigning them to a group taking metronidazole 500 mg orally every 8 h for seven days or an observation group. The primary endpoint was the presence of antibiotic-associated diarrhoea and Clostridium difficile (C. difficile) infection during the seven days of evaluation. The study was approved by the institutional ethics committee. Registration number (11.2017) of 14 March 2017. Results Of the 116 patients who met the inclusion criteria, 96 were analysed, 41 in the intervention group and 55 in the observation group: 4.9% of patients in the intervention group and 16.4% in the observation group developed antibiotic-associated diarrhoea (odds ratio [OR] 0.26 (0.05–1.29); P = 0.109). 0% of patients in the intervention group and 9.1% in the observation group developed C. difficile infection (odds ratio [OR] 0.91 (0.84–0.99); P = 0.069). Conclusions Metronidazole prophylaxis did not result in a reduction in antibiotic-associated diarrhoea. It could, however, be an effective measure for preventing C. difficile infection in selected high-risk patients. This was the first prospective study designed for this purpose. New studies that involve a larger number of patients are required in the future.