Piperacillin/tazobactam in comparison with clindamycin plus gentamicin in the treatment of intra-abdominal infections

Background. Concerned about the inactivation of piperacillin by β-lactamase and the risk of aminoglycoside-induced nephrotoxicity and clindamycin-induced enterocolitis, we conducted the following phase III clinical trial. Methods. Between November 1991 and March 1993, 77 surgical patients with intraabdominal infections were enrolled and randomly assigned in a 3:2 ratio to receive either piperacillin/tazobactam or clindamycin plus gentamicin to compare safety, tolerance and efficacy between both two treatment groups. Results. There were 76 clinically and 50 bacteriologically evaluable patients with 80 isolated pathogens. The demographic data were comparable in both groups. There was no statistically significant difference of clinical response at any time-point of treatment, with 97.8% favorable clinical response rate in piperacillin tazobactam group and 96.6% in clindamycin plus gentamicin group at endpoint. The bacteriological eradication rates were similar, with 97.7% in piperacillin/tazobactam group and 94.4% in clindamycin plus gentamicin group at pathogen level, and 96.7% in piperacillin/tazobactam group and 95.0% in clindamycin plus gentamicin group at patient level. By susceptibility tests, only 3 (4%) isolated pathogens were resistant to piperacillin/tazobactam, which was much superior to the use of piperacillin, clindamycin or gentamicin alone in antimicrobial activity. The piperacillin tazobactam-related adverse experiences included 1 (2.1%) urticaria and 2 (4.3%) diarrhea. However, there were no significant differences in the adverse experiences between these two groups. Conclusions. This study has demonstrated that piperacillin/tazobactam is comparable with clindamycin plus gentamicin in efficacy, safety and tolerance in the treatment of surgical patients with intra-abdominal infections. The combination of piperacillin/tazobactam could potentially be the treatment of choice in adjunct to surgical management in intra-abdominal infection.