Bile bacterial flora and its in vitro resistance pattern in patients with acute cholangitis resulting from choledocholithiasis

Introduction. Cholangitis and biliary sepsis are severe infectious diseases, which are often observed in patients with choledocholithiasis. The antimicrobial therapy is effective if started as soon as the diagnosis is made. Therefore, the profile of bile pathogens and its susceptibility to a number of antibiotics were evaluated. Material and methods. Bile cultures and antibiograms from 92 patients hospitalized between January 2006 and December 2008 in a tertiary referral center for the treatment of biliary and pancreatic diseases (Central Teaching Hospital, Medical University of Silesia) were reviewed. Specimens were obtained from patients with acute cholangitis and confirmed choledocholithiasis during endoscopic (i.e. ERCP) and surgical (i.e. percutaneus transhepatic biliary drainage) procedures. The bile specimens were examined for pathogenic aerobic and anaerobic bacteria and fungi. Results. Sixty-five of 92 analyzed cultures were positive. A total of 69 pathogens were isolated: 47 (68.1%) Gram-negative bacteria, 18 (26.1%) Gram-positive bacteria, 2 (2.9%) anaerobes and 2 (2.9%) Candida. The predominant Gram-negative pathogens were Escherichia coli, Acinetobacter baumani complex, Klebsiella pneumoniae and Enterobacter cloacae. The most effective antibiotics against Gram-negative bacteria were imipenem, cefoperazone/sulbactam, piperacillin/tazobactam and cefepime (susceptibility 97.9%, 89.4%, 85.1% and 85.1%, respectively). The expenditure on antibiotics monotherapies and combined therapies was also analyzed. Conclusion. Our study shows that Gram-negative bacteria were the predominant bile pathogens found in patients with acute cholangitis. Piperacillin/tazobactam or ceftazidime may be the alternative to ciprofloxacin therapeutic option. The addition of ticarcillin/clavulanic acid to ciprofloxacin could also be considered. However, imipenem should remain a back-up antibiotic in the treatment of acute cholangitis.