Abstract
BACKGROUND: Bacterial contamination status may differ under different biliary drainage conditions. The purpose of this study was to determine the impact of qualitative and quantitative biliary bacterial contamination on the incidence of infection complications in patients undergoing pancreatoduodenectomy. METHODS: Patients undergoing pancreatoduodenectomy for periampullary diseases with different biliary drainage conditions, such as external drainage (ED), internal drainage (ID), and no drainage (ND), were included. Bile was collected intraoperatively, and biliary contamination status was qualified and quantified using bacterium-specific ribosomal RNA-targeted reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The impact of biliary contamination status on infection complications was analyzed. RESULTS: A total of 152 patients were included (38 with ED, 40 with ID, and 74 with ND). The positive rate of microorganisms in bile was higher in the ID group (98%) compared with the ED group (82%, p = 0.021) and the ND group (65%, p < 0.001). The number of microorganisms detected in bile samples was higher in the ID group compared with the ED group (median 489,788 vs. 5375 bacteria/mL of bile, p < 0.001). With multivariate analysis, soft pancreas, intraoperative bleeding (> 600 mL), and biliary contamination by Atopobium cluster were identified as independent risk factors for infection complications. Biliary contamination by Atopobium cluster was significantly higher in the ID group compared with the other groups. CONCLUSIONS: Biliary bacterial contamination is more frequently induced by ID than either ED or ND. In addition to the previously known risk factors, biliary contamination with Atopobium cluster may be one of the risk factors of infection complications following pancreatoduodenectomy.