Preoperative Enterosignatures Predict Surgical Site Infections After Abdominal Surgery

The relationship between preoperative intestinal microbiota composition and the development of surgical site infections (SSIs) following abdominal surgery is not well understood. The aim of this study was to characterize the preoperative rectal microbiota using the novel concept of enterosignatures (ESs) in patients undergoing abdominal surgery and assess their association with SSIs.

In this prospective cohort study, preoperative rectal microbiota from 133 patients undergoing elective abdominal surgery was profiled using 16S rRNA sequencing. ESs were calculated using high-quality genus-level taxonomy, simplifying complex microbial compositions into 5 generalizable patterns: Bacteroides-, Firmicutes-, Prevotella-, Bifidobacterium-, or Escherichia-dominated profiles.

A total of 519 bacterial species were identified within the 133 patients. The Firmicutes ES was found to be a significant risk factor for SSIs, while the Prevotella ES was associated with a reduced risk of SSIs. Combining these into the Firmicutes-to-Prevotella ES ratio (ES-Firm-Prev ratio) yielded a stronger association with SSIs (noSSI: median [interquartile range {IQR}] log ES-Firm-Prev ratio, 0.21 [-0.43 to 1.33]; vs SSI: median [IQR] log ES-Firm-Prev ratio, 8.24 [2.17 to 8.5]; P = .001). Machine learning and logistic regression models confirmed the ES-Firm-Prev ratio to be a significant, independant predictor of SSIs (odds ratio, 1.35; 95% CI, 1.09-1.66; P = .005).

The ES-Firm-Prev ratio is a robust, independent predictor of SSIs in patients undergoing abdominal surgery and may serve as a novel biomarker to identify high-risk patients preoperatively.