Factors that Influence the Pancreatic and Duodenal Microbiome in Patients Undergoing Pancreatic Surgery

Abstract

Introduction: This study examined the correlation between the pancreatic microbiome and patient characteristics. Furthermore, we compared different duodenal materials to examine their reflection of the pancreatic microbiome. Method: Patients undergoing pancreatic surgery were included and their clinical data was prospectively registered. Sterile pancreatic biopsies were collected during surgery and after completion of the resection, duodenal fluid, tissue and swab were collected. Bacterial DNA was extracted and analyzed with IS-pro assay. Results: Paired samples of 51 patients were available for evaluation, including pancreatic biopsies from all patients, 22 duodenal juices, 21 duodenal swabs and 11 duodenal tissues. The pancreatic microbiome consisted mostly of Proteobacteria followed by Firmicutes and Bacteroidetes. On species level, Enterococcus faecalis, Escherichia coli, Enterobacter-Klebsiella and Steptococcus mitis group were most abundant. The total bacterial load and Proteobacteria load were significantly higher in patients with biliary drainage (54618.0 vs 5623.5; 9119.0 vs 2067.1 respectively). Patients who used proton pump inhibitors had a significantly higher total bacterial load (115964.7 vs 8495.8), more Firmicutes (66862.9 vs 1890.1), more Proteobacteria (24245.9 vs 2951.4) and more Bacteroidetes (542.5 vs 25.8). The head of the pancreas contained significantly more bacteria (21193.4 vs 2096.8) and more Firmicutes (5225.7 vs 19.0) compared to the tail, regardless of biliary drainage. Furthermore, the microbiome of duodenal materials showed a weak correlation with the pancreatic microbiome. Conclusion: Biliary drainage, use of proton pump inhibitors, and anatomic location of the pancreatic biopsy influence the pancreatic microbiome. Finally, the duodenal microbiome does not suffice as a surrogate for the pancreatic microbiome.