Polymicrobial infection in acute biliary infection: clinical impact, resistance, and risk factors
Year: 2026
Type: article
Study design: Observational Study
Abstract: Background Polymicrobial infection is frequently observed in acute biliary infection; however, its clinical significance, antimicrobial resistance patterns, and associated risk factors remain incompletely understood. Methods This retrospective study included patients with acute biliary infection who underwent endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic gallbladder drainage (PTGD) with bile culture between August 2020 and August 2023. Patients were categorized into monomicrobial and polymicrobial infection groups based on bile culture results. Clinical characteristics, microbial profiles, antimicrobial resistance patterns, and inflammatory severity were compared between groups. Multivariate logistic regression analyses were performed to identify factors associated with systemic inflammatory response syndrome (SIRS), sepsis, and polymicrobial infection. Results A total of 208 patients with acute biliary infection were included, among whom 61 (29.3%) had polymicrobial infection. Gram-negative bacteria predominated in both groups, with Escherichia coli being the most common pathogen. Compared with monomicrobial infection, polymicrobial infection exhibited a relatively higher proportion of Gram-positive organisms. Patients with polymicrobial infection had significantly higher rates of SIRS and sepsis, and polymicrobial infection was independently associated with both SIRS and sepsis. Antibiotic resistance was significantly more common in the polymicrobial group. Among Escherichia coli isolates, resistance rates to several commonly used antibiotics were higher in polymicrobial infection, whereas no significant differences were observed for Klebsiella pneumoniae or Enterococcus faecium . However, antimicrobial resistance itself was not independently associated with SIRS or sepsis. A history of biliary surgery was identified as independent risk factors for polymicrobial infection. Conclusions Polymicrobial infection was independently associated with more severe clinical manifestations and a greater antimicrobial resistance burden in acute biliary infection. Prior biliary surgery may help identify patients at increased risk of polymicrobial infection and inform early risk stratification and empirical antimicrobial selection.
Language: English
Subfield: Gastroenterology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,801
OpenAlex ID: W7223394453