Timing and type of bacteria in surgical site infections following complex abdominal wall reconstruction

Purpose: The goal of this study was to assess the bacteriology of surgical site infections (SSIs) in patients undergoing complex abdominal wall reconstruction (CAWR) with biologic mesh. Methods: This was a prospective cohort study of all patients who developed SSI following CAWR with biologic mesh between 2017-2020 at an academic tertiary/quaternary care center. The patients were subdivided into six overlapping groups: infections found during hospitalization vs. infections found after discharge, sensitive bacteria vs. resistant bacteria, and nosocomial bacteria vs. intestinal bacteria. Results: Of the 194 patients who underwent CAWR during the study period, 33 (17%) developed SSI. SSI was more commonly discovered after discharge than during hospitalization. These SSIs were vancomycin-resistant Enterococcus (VRE) or methicillin-resistant Staphylococcus aureus (MRSA) rather than sensitive bacteria, and required re-operation, which were more frequently found following elective procedures. VRE and MRSA infections were more common with clean wounds than with clean/contaminated, contaminated, or dirty wounds, while SSIs with intestinal flora were more common following fistula and stoma takedown. Conclusions: Surgical site infections with resistant bacteria manifest more frequently post-discharge and require more re-admissions and re-operations.