Revealing the role of early peripancreatic bacterial contamination and Enterococcus faecalis in pancreatic fistula development after pancreaticoduodenectomy: Implications for useful antibiotic prophylaxis–An observational cohort study

Background Peripancreatic bacterial contamination (PBC) is a critical factor contributing to the development of clinically relevant postoperative pancreatic fistula (CR-POPF) following pancreaticoduodenectomy (PD). Controlling pathogenic bacteria is essential in preventing CR-POPF; however, the precise relationship between specific bacteria and CR-POPF remains unclear. This study aimed to investigate the relationship between PBC and CR-POPF after PD, with a focus on identifying potentially causative bacteria. Methods This prospective observational study enrolled 370 patients who underwent PD. Microbial cultures were routinely collected from peripancreatic drain fluid on postoperative days (PODs) 1, 3, and 6. Predictive factors for CR-POPF and the bacteria involved in PBC were investigated. Results CR-POPF occurred in 86 (23.2%) patients. In multivariate analysis, PBC on POD1 (Odds ratio [OR] = 3.59; P = 0.005) was one of the main independent predictive factors for CR-POPF, while prophylactic use of antibiotics other than piperacillin/tazobactam independently influenced PBC on POD1 (OR = 2.95; P = 0.010). Notably, Enterococcus spp., particularly Enterococcus faecalis, were significantly isolated from PBC in patients with CR-POPF compared to those without CR-POPF on PODs 1 and 3 (P < 0.001), and they displayed high resistance to all cephalosporins. Conclusions Early PBC plays a pivotal role in the development of CR-POPF following PD. Prophylactic antibiotic administration, specifically targeting Enterococcus faecalis, may effectively mitigate early PBC and subsequently reduce the risk of CR-POPF. This research sheds light on the importance of bacterial control strategies in preventing CR-POPF after PD.