Etiology and risk factors for biliary tract infection

Objective To investigate the distribution, drug resistance of bile pathogenic bacteria, and the risk factors for biliary infection. Methods Clinical and laboratory data of patients hospitalized from January 2008 to October 2015 were reviewed for pathogenic bacteria and drug resistance, and the factors related to biliary tract infection were studied. Results Among all 320 cases, there were 249 cases of pathogenic bacteria in bile specimens, the positive rate was 77.81%. There were 356 strains of pathogenic bacteria of 40 species, including 244 strains of gram negative bacteria (68.54%), 93 strains of gram positive bacteria (26.12%) and 19 strains of fungi (5.34%). Top three bacteria were Escherichia coli (84 strains, 23.60%), Klebsiella pneumonia (60 strains, 16.85%), and Enterococcus faecium (40 strains, 11.24%). The Escherichia coli and Klebsiella pneumoniae had the highest drug resistance to cefazolin, and they had a lower drug resistance to cefoxitin and amikacin. The multivariate analysis showed that age≥60 years (AOR=2.311, 95%CI: 1.292-4.135)and the history of ERCP operation (AOR=3.475, 95%CI: 1.587-7.607) were independent risk factors for biliary tract infection. Conclusion Bacteria are mainly gram negative bacteria in the bile of patients with biliary tract infection, suggesting antibiotics with low resistant rate of gram-negative is the first choice. The age≥60 years and history of ERCP surgery are independent risk factors for patients with biliary tract disease. Measures to prevent biliary infections in high-risk patients should be taken. Key words: Biliary tract diseases; Bile; Bacteriology; Drug resistance; Risk factors