gms | German Medical Science

Background: Patients with malignant obstructive jaundice often receive preoperative biliary drainage (PBD). Recently, increased postoperative complications were linked to contamination of the bile facilitated by PBD. However, the effect of biliary stenting on the microbiome of the biliary tree and its effect on postoperative outcome is still a neglected important clinical issue.

Materials and methods: Thus a retrospective database analysis of patients with malignant obstructive jaundice 07/2007-07/2014 was performed. Intraoperative microbiological bile samples were obtained after transection of the CBD. Postoperative complications were graded according the Clavien-Dindo classification and pancreatic fistula with the ISGPF classification.

Results: Database search yielded 164 (60.3%) stented and 108 (39.7%) non-stented patients. Contamination of bile fluid was increased in stented patents (97.6% vs. 20.4%; p<0.001). PBD resulted in a switch of the biliary microbiome from E. coli in non-stented patients (45.5% vs. 20%; p<0.05) to E. faecalis (9.0% vs. 38.1%; p<0.01) and E. cloacae (0 % vs. 18.8 %; p<0.05) in biliary drained patients, resulting in enhanced incidence of bacterial resistance against Ampicillin/Sulbactam (61.9% vs. 18.2%; p<0.001), Piperacillin/Tazbactam (27.5% vs. 0%; p<0.01), Ciprofloxacin (28.5 % vs. 5.3 %; p<0.05) and Imipenem (25.8% vs. 0%; p<0.01). Wound infections were significantly augmented after PBD (5.8% vs. 21.2%; p<0.001) and contamination of the bile with E.faecalis (p=0.011), E.faecium (p<0.01), Klebsiella (p=0.014) or Citrobacter (p=0.001) resulted in more frequent wound infections.

Conclusion: This study emphasizes the crucial role of PBD in development of postoperative infectious complications by facilitating a shift of the biliary microbiome towards a more resistant and aggressive spectrum.