Is neomycin necessary for bowel preparation in surgery of the colon? Oral neomycin plus erythromycin versus erythromycin-metronidazole.

In 132 patients who underwent elective surgery of the colon, the value of bowel preparation with a conventional oral antibiotic preparation of neomycin-erythromycin (N-E) was compared with erythromycin-metronidazole (E-M). Of 125 patients who were available for assessment, 61 received N-E and 64 E-M. The two groups were evenly matched. Two wound infections occurred in patients receiving E-M, neither due to anaerobic bacteria, but seven wound infections developed in patients given N-E (p = 0.057), five of them caused by anaerobic bacteria. Anaerobic bacteria of the colon are the dominant cause of postoperative wound infection in elective surgery of the colon. Adequate antibiotic preparation directed against these bacteria makes the use of neomycin unnecessary.