Change of pathogens in patients with biliary tract infection treated in a single center during the past 30 years

Abstract

Objective To investigate the changes of pathogens and antimicrobial susceptibility in patients with biliary tract infection during the past 30 years. Methods During the periods of 1981-1984, 1988-1998 and 2003-2013, each 100 patients treated with common bile duct exploratoration were selected from every period. Biopsied bile specimens were performed with bacteria culture and antimicrobial susceptibility tests. This study reviewed the changes in bilary pathogens and antimicrobial susceptibility test. Results From 1981 to 1984, the most common pathogens were Escherichia coli (59.2%) and Klebsiella pneumonia (28.9%). Mixed infection of these pathogens accounted for 16.9%. From 1988 to 1998, the types of pathogens significantly increased. Escherichia coli (33.1%) and Klebsiella pneumonia (16.5%) accounted for less than 50%. Mixed infection with Escherichia coli and Pseudomonas aeruginosa was the most common type. From 2003 to 2013, gram-negative bacteria were still the main pathogens, accounting for 61.8%. Escherichia coli and Pseudomonas aeruginosa accounted for 20.1% and 10.4%, respectively. Gram-positive bacteria increased significantly. Enterococcus faecium (22.2%) ranked the first. Mixed infection increased (36%), of which more than 50% was mixed pathogens of Escherichia coli and Enterococcus faecium. The incidence of fungi infection also increased (5.6%). Conclusions There was a remarkable change of pathogen category in the biliary infections over the past years. With an increase of gram-positive bacteria and fungi infection in clinical practice, antimicrobial susceptability results could be considered in choosing appropriate drug to avoid bacterial resistance. Key words: Biliary tract infection; Pathogen; antimicrobial susceptibility test; Resistant rate