Preoperative Intestinal Microbiota Profiles Predict Surgical Site Infections After Abdominal Surgery

Overview

This prospective cohort study of 133 patients undergoing elective abdominal surgery identified that preoperative intestinal microbiota enterosignatures (ESs) are associated with surgical site infection (SSI) risk. Specifically, a higher Firmicutes-to-Prevotella ES ratio strongly predicted increased SSI incidence, serving as an independent biomarker for postoperative infection risk.

Background

Surgical site infections (SSIs) remain a common complication after abdominal surgery, occurring in approximately 10% of cases despite antiseptic measures. The intestinal microbiota plays a critical role in maintaining the intestinal barrier and preventing infections, but its relationship with SSIs is not well defined. Previous studies have linked specific bacterial species or community structures with postoperative complications, but individual microbiota variability limits generalizability. The novel concept of enterosignatures (ESs) categorizes intestinal microbiota into five dominant patterns, potentially enabling broader clinical application.

Data Highlights

Key Findings

• Preoperative rectal microbiota profiling identified 519 bacterial species across 133 patients undergoing abdominal surgery.
• The Firmicutes-dominated enterosignature (ES-Firm) was significantly associated with increased SSI risk.
• The Prevotella-dominated enterosignature (ES-Prev) was associated with a reduced risk of SSIs.
• The combined Firmicutes-to-Prevotella ES ratio (ES-Firm-Prev ratio) showed a stronger association with SSI risk than individual ESs.
• Machine learning and logistic regression confirmed the ES-Firm-Prev ratio as an independent predictor of SSIs (odds ratio 1.35; 95% CI 1.09–1.66; P=0.005).
• The ES model provides a generalizable framework to simplify complex microbiota data into clinically relevant patterns.

Clinical Implications

Preoperative assessment of intestinal microbiota enterosignatures, particularly the Firmicutes-to-Prevotella ratio, may help identify patients at higher risk for surgical site infections following abdominal surgery. This biomarker could guide targeted preventive strategies or tailored perioperative management to reduce SSI incidence. Incorporating microbiota profiling into preoperative evaluation may enhance risk stratification beyond traditional clinical factors.

Conclusion

The Firmicutes-to-Prevotella enterosignature ratio is a robust, independent predictor of surgical site infections after abdominal surgery. This novel biomarker offers potential for improved preoperative risk assessment and personalized infection prevention strategies.

References

1. Frioux et al. 2023 -- Enterosignatures: Generalizable Intestinal Microbiota Patterns
2. CDC 2017 -- Surgical Site Infection Criteria