An Antimicrobial Stewardship Program in Pancreatic Surgery Reduces the Infectious Risk of Colonized Bile, Reducing the Predictive Value of the Intraoperative Bile Culture

Objective: To evaluate the pancreatic surgery-specific antimicrobial stewardship (AMS) program on surgical site infections (SSIs), focusing on bile microbiology and colonization. Background: Colonized bile is well known to increase the risk of SSIs after pancreatoduodenectomy. However, AMS programs seem to reduce their occurrence. Methods: This observational before-after study included patients who underwent pancreatoduodenectomy from 2015 to 2022 at a high-volume pancreatic center (#NCT04199494). Pre-AMS data spanned from January 2015 to November 2019, and post-AMS data from December 2019 to October 2022. Intraoperative bile samples were analyzed for microbiology. The AMS program involved preoperative rectal screening for multidrug-resistant bacteria to guide personalized surgical antibiotic prophylaxis (SAP). Tailored SAP was used for patients colonized with resistant pathogens. SSI rates, length of stay, major and pancreatic surgery-specific complications, and mortality were assessed using standard statistics. Results: Of 1638 patients included, 1321 (80.6%) had intraoperative bile sampling, with 909 samples (68.8%) testing positive for colonization. The most common bacteria were Enterobacterales (75%), 18% extended-spectrum beta-lactamase–producing, and Enterococci (60%), 4% of which were vancomycin-resistant. Colonized bile was associated with male sex, jaundice, biliary stenting, and positive rectal screening ( P < 0.05). Before AMS, colonized bile correlated with higher SSI rates (38% vs 31%, P = 0.008). Post-AMS, no significant difference was observed (29% vs 28%, P = 0.5). Tailored SAP reduced overall SSI (34% reduction, P = 0.002) and superficial SSI (59% reduction, P = 0.011). Conclusions: Pancreatic surgery-specific AMS with tailored SAP reduces SSIs and diminishes the predictive value of colonized bile for SSIs. Intraoperative bile cultures remain valuable for postoperative management.