Analysis of bacteria in the bile of patients with biliary tract cancer and cholelithiasis

Objective To investigate the relationship between gallstone formation and bacterial infection. Methods Bile was collected aseptically from patients with biliary tract cancer and cholelithiasis. Bile was cultured aerobically, anaerobically and microaerophilically, then API identification and bacteria flora analysis were carried out. Results The positive rate of bacteria in biles of patients with cholelithiasis, cholelithiasis combined with biliary tract cancer and biliary tract cancer was 36%(34/95), 43%(6/14) and 57%(8/14) respectively. In pigment stone type, mixed gallstone type, cholesterol gallstone type and unknown gallstone type, the positive rate for bacteria was 77%(10/13), 29%(16/56), 23%(3/13) and 45%(10/22) respectively. 69 strains of bacteria were detected including 30 strains of Enterobacteriaceae, 19 strains of Enterococcus and others including Staphylococcus, Streptococcus etc. Conclusions Bacteria are isolated in bile of cholelithiasis patients and the positive rate of pigment stone type is the highest. The main kind flora in bile is Enterobacteriaceae and Enterococcus. The results show that pigment stone type formation may be related to bacteria infection.