Bacterial Colonization in Resected Lymph Nodes during Pancreatic Surgery: A Pilot Study

Abstract

Introduction: The detection of bacterial colonization in postoperative pancreatic fistula (POPF) fluid has renewed interest in the role of bacterial translocation during pancreatic surgery. In this context, we hypothesized that peripancreatic lymph nodes (PLNs) might similarly harbor bacterial colonization. This study aimed to investigate the presence of bacteria in these lymph nodes, identify factors potentially contributing to their colonization, and assess the clinical significance of these findings. Methods: In this observational pilot study, PLNs (station 8a) resected during pancreatic surgery were analyzed for bacterial DNA using 16S rDNA-PCR, and the microbiological findings were correlated with detailed perioperative and postoperative clinical data. Results: Between 2019 and 2026, lymph node station 8a was resected and analyzed in 37 patients undergoing pancreatic surgery. Bacterial colonization was found in 3 patients (8.1%). No significant association was observed between lymph node colonization and the type of surgical procedure, histopathological diagnosis, or the development of clinically relevant POPF or other major postoperative complications. All cases with bacterial colonization had undergone preoperative endoscopic retrograde cholangiopancreatography (ERCP; p = 0.230). Conclusion: In this pilot study, bacterial colonization of PLNs was uncommon and was observed only in patients with a history of ERCP. Although no association with POPF was identified, a potential relationship with overall postoperative morbidity cannot be ruled out. Further studies with larger patient cohorts are needed to better define the clinical relevance and underlying mechanisms of lymphatic bacterial translocation.