Fosfomycin/metronidazole compared with doxycycline/metronidazole for the prophylaxis of infection after elective colorectal surgery. A randomised double-blind multicentre trial in 517 patients.

OBJECTIVE: To find out if fosfomycin together with metronidazole was any better than doxycycline with metronidazole for the prophylaxis of infection before elective colorectal operations. DESIGN: Multicentre, double blind, random control trial. SETTING: Nine Swedish hospitals. SUBJECTS-559 patients admitted for elective colorectal operations. INTERVENTIONS: Fosfomycin 8 g and metronidazole 1 g before operation and fosfomycin 8 g eight hours afterwards, or doxycycline 400 mg and metronidazole 1 g before operation, and placebo eight hours afterwards. MAIN OUTCOME MEASURES: Incidence of all types of infection, mortality, and side effects. RESULTS: There were no significant differences between the groups for any of the outcome measures studied, the overall abdominal infection rates (wound, deep, and septicaemia) being 4.6% and 7.4%, and the remote infection rates (pneumonia, urinary tract, and central venous line) 15.1% and 12.8%, respectively. Of the predictors studied, only duration of operation was significantly related to risk of infection. CONCLUSION: The combination of fosfomycin and metronidazole was as safe and effective as that of doxycycline and metronidazole in preventing infections after elective colorectal operations.