Antibiotic prophylaxis and empirical therapy for intra-abdominal infections: a systematic review and network meta-analysis

INTRODUCTION: This network meta-analysis (NMA) compared the efficacy and safety of antibiotic classes for empirical treatment of suspected intra-abdominal infections (IAIs) and for prophylaxis in at-risk populations. METHODS: PubMed, Embase, SCOPUS, Web of Science, and CENTRAL were searched until 24 January 2026 (PROSPERO-CRD420251106514). Eligible studies assessed empiric antibiotic therapy or prophylaxis for IAI. Outcomes included treatment success, intra-abdominal and wound infection rates, morbidity, mortality, and adverse events. Treatment and prophylaxis data were analyzed as separate networks per outcome using frequentist random-effects NMA, with certainty graded via GRADE. RESULTS: 19 studies (2,910 patients) on treatment and 9 studies (3,014 patients) on prophylaxis, across eight antibiotic classes, were included. In treatment setting, carbapenems were associated with significantly higher treatment success than β-lactam/β-lactamase inhibitor [RR(95%CI)=1.06 (1.01-1.62)], and ranked highest by SUCRA for treatment success and adverse events. In prophylaxis setting, cephalosporin was associated with a lower risk of wound infection than carbapenem [RR(95%CI)=0.79 (0.70-0.88)] and β-lactam/β-lactamase inhibitor [RR(95%CI)=0.38 (0.16-0.91)]. Sensitivity analyses confirmed robustness; certainty ranged from moderate to very low, mainly due to imprecision. CONCLUSION: Carbapenems provide the highest efficacy for empirical IAI treatment but require judicious use given resistance concerns. This benefit does not extend to prophylaxis, where narrower-spectrum agents such as cephalosporins performed well. Further high-quality trials incorporating newer agents and resistance outcomes are needed.