Microbiological analysis of patients with first and recurrent episodes of acute cholangitis in a middle-sized hospital: A single-center retrospective study in rural North Kyoto, Japan

Background Knowledge of the bacterial spectrum involved in acute cholangitis is essential for adequate empiric antibiotic treatment. There is a lack of published data comparative data between patients with first and recurrent episodes of acute cholangitis. This study aimed to analyze the microbial spectrum in patients with first and second episodes of acute cholangitis. Methods We retrospectively assessed 251 patients with first episodes of acute cholangitis between January 2014 to September 2020. Results At the first episode of acute cholangitis, the predominant strains belonged to Escherichia coli (17.9%), followed by Klebsiella spp. (15.5%), Enterobacter spp. (6.4%), and Enterococcus spp. (5.6%). During follow-up, acute cholangitis recurred in 109 patients; at the second episode, the predominant strains belonged to Enterococcus spp. (35.8%), followed by Klebsiella spp. (27.5%), Enterobacter spp. (22.9%), and Escherichia coli (15.6%). Enterococcus spp. were the most common pathogen in patients with second episode of acute cholangitis, regardless of whether the cholangitis was caused by a malignant tumor or a benign disease. Conclusions Unlike in patients with a first episode of acute cholangitis, clinicians should consider empirical treatment with anti-enterococcal antibiotics in patients with recurrent episodes of acute cholangitis.