Prevalence, Resistance Rates, and Risk Factors of Pathogens in Routine Bile Cultures Obtained during Endoscopic Retrograde Cholangiography.

INTRODUCTION AND OBJECTIVE: Acute cholangitis is a life-threatening condition. The early initiation of antibiotic therapy significantly impacts the course of disease. Only few data are available on distribution and resistance profiles of bile pathogens. Here, we report on an analysis of routinely acquired bile specimens and provide an overview of the prevalence, resistance rates, and risk factors for the presence of pathogens in bile. METHODS: Bile cultures obtained from 388 endoscopic retrograde cholangiographies (ERCs) with corresponding clinical data were analysed in 208 patients. RESULTS: The majority (84.8%) of cultures yielded positive for at least 1 organism. Abundance was highest for Enterococcus faecalis, Enterococcus faecium, and Escherichia coli. Multiresistant organisms were present in 14.9%. The initial antibiotic regimen was changed in 44.1%, which increased the length of hospital stay significantly (***p < 0.001). Pre-existing papillotomy (EPT) or biliary drainage was associated with higher frequency of bile pathogens (**p < 0.01) in a univariate analysis. Multivariate analysis confirmed these results for EPT and revealed significantly more positive results for pathogens, gram-negative bacteria, and fungi in patients with biliary drainage. Significant differences in the prevalence of pathogens were observed between relevant subgroups of ERC indications. The highest susceptibility rates were observed for linezolid and tigecycline in gram-positive bacteria and for meropenem and gentamicin in gram-negative bacteria. CONCLUSIONS: Our study provides a comprehensive analysis of the distribution, resistance profiles, and risk factors for the detection of bile pathogens. The frequent change in initial antibiotic treatment highlights the importance of routine bile culture and indicates that current schemas of empirical treatment might not cover the contemporary spectrum of pathogens in bile.