Microbiological Characteristics of Pathogens Isolated From Blood Cultures of Patients With Acute Cholangitis: Insights From Patients With Biliary‐Enteric Anastomosis

ABSTRACT Background We aimed to investigate the microbiological characteristics of pathogens isolated from blood cultures (BCs) of patients with acute cholangitis (AC) after biliary‐enteric anastomosis and biliary intervention (BI). Methods A retrospective analysis was conducted on 366 patients with AC and bacteremia between 2015 and 2024 at Hiroshima University Hospital. Patients were categorized into three groups: post‐biliary reconstruction‐associated AC (PBR‐AC), BI‐associated AC (BI‐AC), and common AC (C‐AC). Patients' clinical and microbiological data were statistically analyzed in each group. Results The most frequently isolated pathogens were Escherichia coli and Klebsiella spp., accounting for > 50% of isolates in all groups. ESCPM spp. ( Enterobacter spp., including Klebsiella aerogenes , Serratia marcescens , Citrobacter freundii complex , Providencia spp., and Morganella morganii ) were significantly associated with PBR‐ and BI‐AC compared with C‐AC. No significant differences in the prevalence of anaerobic bacteria were observed among the groups. Conclusions The prevalence of ESCPM spp. isolated from BCs was significantly higher in the PBR‐ and BI‐AC groups than in the C‐AC group. The presence of biliary‐enteric anastomosis or BI history should be checked when determining the treatment strategy for AC. Cefepime may be a better antibiotic option for PBR‐ and BI‐AC, particularly in severe cases.