Abstract:Objective To explore the distribution of bacterial flora in bile of elderly patients with biliary tract infection and the resistance of common bacterial flora to provide more reliable theoretical guidance for clinical treatment.Methods By percutaneous transhepatic gallbladder drainage,percutaneous transhepatic biliary drainage or biliary tract surgery,the bile specimens were collected for bacteriological culture and bacterial identification from 100 patients with biliary tract infection treated from January 2017 to December 2017 (observation group),and 100 cases of healthy subjects with physical examination over the same period were selected as control group.By automatic biochemical analyzer and ELISA,the serum level of CRP and IL6 and TNFα were detected,respectively and compared between two groups.Results In 100 bile specimens,there were 85 cases cultured for bacterial growth(85.00%) with 102 strains of pathogenic bacteria,in which 92（90.20%）isolates were Gramnegative bacteria.Drug sensitivity testing suggested that most Gramnegative bacteria had high sensitivity to imipenem and meropenem,and most common pathogenic bacteria had higher drug resistance to the second and third generation of antibiotics,10 strains of Grampositive bacteria were 100% sensitive to teicoplanin.In the antibiotics used in the firstline treatment,the drug resistance rates of erythromycin(77.78%) and ampicillin(66.67%) were the highest.The serum levels of IL6,TNFα and CRP in observation group were significantly higher than those in control group (P<0.01).Conclusions Most of the pathogenic bacteria of biliary tract infection are Gramnegative bacteria in intestinal flora and are highly sensitive to piperacillin and advanced carbapenem.The clinical treatment should be performed fully considering the results of pathogen isolation and culture and drug sensitivity test.